Unlimited smartphone data is back! Roll out the barrels, re-download Netflix, and disable all those "Wi-Fi only" settings options, happy days are here again. But don't throw away your data meter just yet: the new batch of unlimited data plans from American carriers isn't what it used to be. A lack of limits now comes with an asterisk, like your favorite sports star "enhancing" his performance. So the question is no longer, "which mobile unlimited plan is the best?" Instead, it's "which carrier is going to put the least amount of petty restrictions on my so-called unlimited data?"

Let's break it down. Here are the basics on the four major carriers' unlimited plans - what they can do and what they can't, which ones limit music and video quality, which ones allow tethering and how much, et cetera. We also have some alternative picks from smaller carriers and MVNOs, which might be a better choice depending on your circumstances. Fine print: all of these plans include monthly discounts for enabling auto-pay and/or paperless billing. "Throttling" may or may not occur only during times of network congestion.

T-Mobile ONE Unlimited Data

One line price: $70, taxes and fees included

Multi-line prices: two lines for $100, three for $140, four for $160

Throttling: "3% of data users" or over 28GB

Tethering: 10GB LTE, 3G speeds throttled

Music and movies: "HD" streaming cap, can be removed by the user

The original ONE plan was met with quite a bit of skepticism: T-Mo seemed to be abandoning its cheaper tiered plans and forcing new customers onto so-called "unlimited" data with a lot of catches, like video capped at 480p. Customers could remove most of these restrictions and add on extras like high-speed international data. Since Verizon's bullish move, the company has lowered family prices slightly and removed the charge for HD day passes. The Plus option ($5 a line) adds unlimited Gogo in-flight WiFi, and the international version ($25 per line) adds unlimited LTE tethering and unlimited international calls in a ton of countries. T-Mobile offers free data and text in 140 countries with "up to 3G speeds," something most of its competitors can't match. T-Mobile's new taxes and fees included policy is a nice bonus, too.

Verizon Unlimited Data

One line price: $80

Multi-line prices: two lines for $140, three for $162, four for $180

Throttling: over 22GB

Tethering: 10GB LTE, 3G speeds throttled

Music and movies: "HD" streaming cap

Verizon's new deal seems to be the best bang for the buck, at least in terms of coverage - customers get signal that meets or beats AT&T in most places in the country, for only $10 a month more than T-Mobile (before taxes and fees). Big Red doesn't offer the same add-on "plus" features as T-Mobile, but its streaming media is throttled at a non-specific "HD" rate for everyone. Verizon's plan includes calls and texts to and from Canada and Mexico, but other international calls and texts may incur charges.

AT&T Unlimited Plus Data

One line price: $100

Multi-line prices: two lines for $145, three for $165, four for $185 (after bill credit)

Throttling: over 22GB

Tethering: 10GB, 2G speeds throttled

Music and movies: 480p streaming, can be permanently removed on Plus

After more than a year of offering unlimited smartphone data to DirecTV customers only (hey AT&T, monopolistic arm-twisting only works if you actually have a monopoly!), the carrier is now offering it to the poor and the gentry . But with the highest price on the market and the lowest amount of features, AT&T's plan has the dubious honor of being the worst deal in the country. In addition to prices that are $20 more than everyone else, the "fourth line free" promotion only kicks in as a bill credit after "1-2 billing cycles" - so, three months and over $100 in charges that aren't being highlighted in the promotion. In addition there's zero tethering offered, none, zip, nada - a huge drawback when every other major carrier is offering at least some LTE data.

Sprint Unlimited Data

One line price: $60

Multi-line prices: two lines for $100, three for $130, four for $160

Throttling: over 23GB

Tethering: 5GB, 2G speeds throttled

Music and movies: 480p streaming

At the time of writing Sprint is offering a single line of unlimited data for just $50, two lines for $90, and three, four, or five for no extra charge. That's pretty great for families, but not only is the deal a "limited time offer" with no specifics on its date, the prices are only good through March of 2018, after which they're bumped up to the figures listed above. We'll go with the final contracted prices for the sake of comparison, since they're still the lowest among the big four. That said, Sprint's coverage is in a distant fourth place and their phone selection is sub-par, which might make that $10 a month savings versus T-Mobile less attractive. Sprint's unlimited also includes a rather puny 5GB of tethering that's bumped all the way down to 2G speeds once you hit the limit. That's less than ideal for frequent travelers.

Who sucks the least?

Surprisingly, it's Verizon. That's right, the carrier that whined the most frequently and loudly is offering the best unlimited data plan in the country. T-Mobile has them beat for pure price, but the added confusion of not one but two extra tiers for the "ONE" plan, not to mention poorer reception outside of cities, makes Verizon a better choice for new customers. That said, T-Mobile is still the one to go with if you'd like to save a little money. True, it's more expensive than Sprint's non-promo price, but better coverage, phone selection, and tethering terms make it more attractive in the long run.

If there's one thing that everyone can agree on, it's that AT&T's expensive, restrictive unlimited plan should be avoided like the plague. AT&T might offer more reasonable prices and tethering terms after a couple of quarters of customers fleeing for more reasonable options at Verizon. We'll see.

Alternative carriers

Boost Mobile: This Sprint MVNO offers $50 unlimited plans without the promotional rigmarole, though HD video is an extra $20 a month. In addition, Boost offers 8GB of high speed tethering - more than Sprint!

MetroPCS: T-Mobile's in-house prepaid carrier offers a $60 unlimited plan - $10 cheaper than the parent company - with 8GB of tethering included. Data is potentially throttled at slightly higher 28GB, too, and MetroPCS also includes taxes and fees in the monthly sticker price.