LED light bulbs hit a new milestone this year, with 60W replacements selling for less than $5, no rebates necessary. At that price, upgrading from incandescents is a no-brainer, especially considering that an incandescent will add about $7 to your yearly energy bill, compared to just over a buck from a comparable LED.

One of those low-cost options can be found on the shelf at Walmart. Sold under the "Great Value" brand name, the bulb is a dimmable 60W replacement that costs just $4.88 a piece. At that price, the dimmable bit is perhaps its strongest selling point -- comparable low-cost options like the Philips 60W Replacement LED and the GE Bright Stik LED won't dim at all. The Walmart LED is also noticeably brighter than those two, and it promises a longer lifespan of 25,000 hours.

That's enough for me to call this bulb a good purchase, but it isn't a perfect one. Yes, it dims, but it doesn't dim particularly well, and failed to go much lower than 20 percent brightness on any of the dimmers I tested it with (ideally, you want a bulb that'll hit 10 percent or lower). It also flickered a fair amount at those lowest settings, which might be another deal breaker if you like the lights down low. Walmart's LED deserves consideration alongside Philips and GE in that bargain-priced tier, but for smooth, satisfying dimming performance, I'd rather spend a few extra bucks on a bulb like the Osram 60W Replacement LED.

Design and specs

Walmart's Great Value line of LEDs are actually manufactured by TCP, a brand that's impressed us in the past. I was impressed again as I started testing out the dimmable 60W replacement Great Value bulb. With 874 lumens to its name, it's officially the brightest 60W replacement bulb I've tested. The 5,000 K daylight version of the bulb does even better, coming in 100 lumens brighter and putting it closer to 75W replacement territory than 60W.

You get that brightness from a power draw of 10 watts. That's the same as GE Bright Stik and the Ikea Ledare LEDs, but obviously more efficient than either of those two because you're getting more brightness for the power draw -- roughly 87 lumens per watt. The only low-cost LED that beats it in efficiency is the Philips 60W Replacement LED, which also costs $5. That bulb puts out 821 lumens from a power draw of 8.5 watts, giving you nearly 100 lumens per watt.

Walmart's Great Value LED vs. the competition Walmart Great Value 60W Replacement LED GE Bright Stik LED Philips 60W Replacement LED Ikea Ledare LED (frosted) Cree 4Flow LED Lumens (measured / stated) 874 / 800 786 / 760 821 / 800 658 / 600 777 / 815 Watts 10 10 8.5 10 10 Efficiency (lumens per watt) 87 79 97 60 78 Yearly energy cost (3 hr. per day @ .11 kWh) $1.20 $1.20 $1.02 $1.20 $1.20 Color temperature (measured / stated) 2,779 K / 2,700 K 2,830 K / 2,850 K 2,701 K / 2,700 K 2,632 K / 2,700 K 2,619 K / 2,700 K Color rendering index 82 81 80 88 83 Dimmable (measured range) Yes (19.9 - 100%) No (N/A) No (N/A) Yes (6.3 - 100%) Yes (6.1 - 100%) Dimmer switch flicker/buzz Light N/A N/A None Light Lifespan 25,000 hours 15,000 hours 11,000 hours 25,000 hours 30,000 hours Weight 2.90 oz. 1.60 oz. 1.80 oz. 4.10 oz. 1.90 oz. Warranty 3 years 5 years 3 years none 5 years Price $5 $10 (3-pack) $5 $5 $8

Designwise, the bulb is simple and inoffensive looking, sticking to the safe side of LED aesthetics. It's an omnidirectional bulb, which means that it puts light out in all directions. That makes it a good pick for most general lighting needs, and suitable for something like a bedside reading lamp, where downward cast light is especially important.

The bulb also claims a lifespan of 25,000 hours -- well over 20 years if you're using it for an average of three hours a day. That's better than you'll get with most of the LEDs you'll find priced at 5 dollars or less. The Philips 60W Replacement LED only promises 15,000 hours, for instance, while the GE Bright Stik offers even less at 11,000 hours.

Enlarge Image Ry Crist/CNET

Walmart backs the longevity claims with a three-year warranty for each bulb. That offers plenty of buying reassurance, given that it'll pay for itself in less than a year if you're upgrading from an incandescent. Other options do slightly better, though -- you get five years of coverage with the Cree 4Flow LED and the Philips 60W Replacement LED.

Something else worth noting: you'll want to be careful when you're making your purchase, as Walmart offers multiple versions of this bulb with confusingly similar packaging. Different color temperatures aren't color-coded using traditional orange and blue hues, and it's also easy to mistake the dimmable and non-dimmable versions. Make sure you double-check the packaging before ringing up.