Call it the smartphone-shopper's dilemma: If you want a state-of-the-art model like the HTC One M8 or the Samsung Galaxy S5, be prepared to shell out $600 to $700 -- or get in bed with a carrier for another two years in exchange for a subsidized price.

Last year, Google introduced a third option in the form of the Nexus 5, a powerful but unlocked phone starting at $349. Not only was the hardware more affordable, but you could take it to just about any carrier for contract-free service.

Following that same model, here comes the OnePlus One, a bleeding-edge unlocked phone starting at $299. But can a China-based startup really compete with the likes of Google?

Surprise: It does compete effectively with Google -- and with HTC, Motorola and Samsung. The One delivers virtually unrivaled bang for the buck, and although it's not without a few rough edges, it may just be the smartphone Android fanboys have been waiting for.

However, before I get into the details, there's a major caveat: At press time, you need an invitation to place an order. To come by one of those, you need to know someone who has already bought one (early invitees receive additional invitations to hand out). According to the website, there's another possibility: You can try "entering contests and promotional events hosted on our OnePlus Forums or social media channels." Alas, I couldn't track down any of either.

A company rep promised ramped-up production and easier-to-come-by invites as of early July, but wouldn't share any details about a traditional ordering process.

I tested my unit with H2O Wireless, an AT&T mobile virtual network operator (MVNO). Although the One supports both GSM and WCDMA bands, here in the U.S. it's compatible with only AT&T and T-Mobile (and their various MVNOs). Sorry, Sprint and Verizon Wireless fans: It doesn't work with their CDMA networks.

Design

Though svelte and curvy, the One probably won't win any beauty contests, especially if it's competing with the silvery metal likes of an HTC One M8. Even so, I can't help comparing it to the Millennium Falcon: It's got it where it counts.

With its 5.5-in. Gorilla Glass 3 display, the One falls squarely into phablet territory, a term I despise but must apply here. It positively dwarfs an iPhone 5s and yet it's surprisingly thin, with a depth of only 0.35 in. I found the tapered 6-x-3-in. body comfortable to hold, and always expected to feel more heft when I picked it up. At 5.7 oz., the One is incredibly light for its size.

Its non-removable back plate, however, may be the ugliest I've seen on a smartphone. The "sandstone black" color is more of a dark, depressing gray (think: floor mat), and the surface has an almost cloth-like roughness. OnePlus plans to offer cases for the phone, including a couple of snazzy-looking yellow and orange numbers, but they're not available yet. My guess is you'll want one -- and not just for protection.

The power button gets a little lost along the right edge, as it's located roughly two-fifths of the way down from the top and is practically flush with the bezel. Your index finger may light on it when you grip the phone in your left hand, but I still found myself searching for the power button much of the time. On the opposite edge, the volume rocker is similarly slim and hard to locate by touch.

Speaking of hard to find, the One includes three capacitive buttons below the screen. But they're small and non-standard in layout, with the Back button on the right and Menu on the left. Worse still, they're nearly impossible to see owing to barely-there backlighting. I could find no setting for making them brighter. Thankfully, you can toggle an onscreen navigation bar that gives you the "correct" layout and bigger, brighter buttons -- but it does eat into your screen estate a bit.

(There's an ironic upside to this: The three capacitive buttons make the phone a bit easier to operate one-handed, though anyone buying a model with a 5.5-in. display should recognize the inherent difficulties of that proposition.)

The One's other design elements are unremarkable, including a headphone jack on the top edge, a micro-USB port flanked by speakers on the bottom and a camera lens embedded into the upper rear. There's also a multicolor LED, used for notifications, to the left of the earpiece.

Features

On paper, this phone dresses to impress. The Qualcomm Snapdragon 801 quad-core processor powers CyanogenMod 11S, a distribution of Android 4.4 that offers more customization options out of the box than you get from vanilla Android. It's also stocked with 3GB of DDR3 RAM and, oddly, your choice of 16GB of storage ($299) or 64GB ($349). There's no 32GB option, nor is there a micro SD slot. For most users, the choice is obvious: Spend the extra $50.

The phone offers Bluetooth 4.0, dual-band Wi-Fi and NFC.

The IPS LCD screen is a behemoth, of course, but razor-sharp at 1920 x 1080 pixels and 401 pixels per inch. Screen quality can be a subjective thing, but I found the colors vibrant and pleasing, especially in games like Asphalt 8, and was especially impressed by how visible the display remained under bright sunlight (so long as you crank the brightness to maximum).

However, viewed alongside an iPhone 5s with the Kindle app running on both, it's clear which screen delivers brighter whites. Would you find the One's slightly yellow-tinged display disappointing in day-to-day use? I didn't, and I read a lot of stuff on the Web. Just be aware it's not the whitest LCD out there.

One example of the aforementioned CyanogenMod goodness: You can adjust screen brightness by swiping left or right along the omnipresent status bar. Another: Double-tapping the screen wakes the phone (a nice workaround for that hard-to-find power button) and drawing a "V" -- even when the screen is off -- toggles the dual-LED flashlight.

Camera

Those LEDs also provide the lighting for the One's rear camera: the impressive-sounding Sony Exmor IMX214 with f/2.0 aperture. It employs a 13-megapixel sensor and those dual LEDs promise extra lighting in dark environments -- though it's not as sophisticated as the iPhone 5s' True Tone system, so the camera is really just blasting extra light (usually to the subjects' detriment).

The front camera does a better-than-average job snapping selfies thanks to its wide-angle lens, which captures a wider field of view than, say, my iPhone 5s.

As for video, the One can capture not only 1080p, but also ultra-high definition (UHD -- also known as 4K and 2160p). It offers a 120fps slow-motion mode as well, though this requires you to downshift from 1080p to 720p -- a fact you discover only after trying to record at 1080p, at which you're limited to 60fps. (OnePlus needs to tweak the software so you can't select 120fps if you've also selected 1080p.)

The CyanogenMod Camera app is a joy to use, with clear onscreen controls and plenty of scene modes. You can select one of the latter via a typical menu, but it also lets you swipe up and down in the viewfinder to quickly "dial" through the available modes. That's so much faster than venturing into a menu over and over again until you find a scene setting you like.

After shooting in a variety of low-light and indoor/outdoor settings, I can attest that, while colors felt a bit muted and exposure wasn't always consistent, overall, the camera performed admirably. Low-light shots in particular were nearly as good as those captured with an iPhone 5s, and 120fps video -- even at the lower resolution -- looked silky-smooth. I'm fairly forgiving when it comes to smartphone photography, coveting convenience and versatility over perfect color accuracy, and I had few complaints with the One's camera.

In fact, the only real downside I discovered was a lengthy shutter lag (1-2 seconds, I'd say) when shooting in low light with the flash enabled.

Performance

The OnePlus One is as fast and responsive as any phone I've used. Apps loaded anywhere between instantly and quickly, though that's hardly the most telling indicator of performance. My preferred informal test is to run about a dozen apps simultaneously, then fire up the browser and see if there's any lag when I zoom in or out. Here, there was zero: The screen immediately snapped to whatever size I chose.

At a Glance OnePlus One OnePlus Price: $299 Pros: Big, beautiful screen; screaming processor; great battery life, smart CyanogenMod deployment; unlocked for use with GSM networks, half the price of competing unsubsidized phones Cons:Unappealing backplate; muted colors from the camera; not compatible with CDMA networks; not available except with invite

Battery life has long been one of my chief complaints with Android devices, especially when it comes to simple idling: I can leave a half-charged phone on my nightstand and wake up to find it dead. Not so the One: Even when I barely touched it for a couple days, it retained most of its charge. And on days when I used it heavily, it survived from morning till night with power to spare. Its 3,100mAh battery can't be removed, but I suspect few users would bother to carry a spare anyway.

Heading into this review, I'd read some reports indicating low call volume on preproduction Ones. My unit had no such problems; callers came through loud and clear, and reported similarly good voice quality at their end. Speakerphone calls were sufficiently loud, but otherwise unremarkable. The embedded pair of speakers also produced decent, if not especially loud, audio for the likes of games and music, though, as with most phones, your grip can end up muffling or redirecting the sound.

Bottom line

What really constitutes a "premium" smartphone nowadays? Is it metal construction? Advanced features like waterproofing and wireless charging? The OnePlus One offers none of those amenities, yet there's no question this is a high-end handset, one packed with a powerful processor, a beautiful screen, tons of storage and a really good Android experience in the form of CyanogenMod.

And that price. The best comparison is the unlocked Google Nexus 5, which starts at $349 for the 16GB model. (It's $399 for 32GB, but there's not even a 64GB version available.) It has a similar processor to the One, but also a smaller screen and battery. On the flipside, it's a prettier phone, at least from the rear, and it delivers unmodded Android, which some users are sure to prefer.

However, the hardcore Android crowd positively reveres CyanogenMod, and with good reason: It's easy on the eyes, full of clever contrivances and endlessly hackable. That it's baked into the One's DNA will be reason enough for the techie crowd to buy in.

For everyone else, there are plenty more reasons. The One instantly joins the ranks of powerhouse Android phones, but sets itself apart with a much lower price. In fact, if it's a phablet you're after, nothing else comes close.

Although right now, the real problem to getting a OnePlus One is -- getting a OnePlus One.

This article, OnePlus One deep-dive review: Unbeatable value for Android geeks, was originally published at Computerworld.com.