The milkshake has been a favorite drive-through dessert item for decades. It's just about perfect: You can drink it while you're driving, choose your own flavor and, since it's made from milk, delude yourself into thinking it's not really all that bad for you.

Milkshakes weren't always so healthy, though. In their original form, which debuted shortly before the turn of the 20th century, they were mixtures of spices, eggs, whiskey and various other largely unmentionable ingredients that were supposedly good for you. The health benefits likely came from the purgative effect of learning the ingredients of what you'd just quaffed.

Over time, the milkshake developed into what we know today: milk, ice cream and flavorings blended together to make a smooth concoction that is best consumed first with a long-handled spoon, then a straw as it melts a bit.

Of course, the time it takes to scoop out ice cream, add milk and flavorings and blend it all together simply doesn't work in a fast-food world where managers' bonuses can stand or fall based on time-of-service averages. Thus, with a couple of notable exceptions, the fast-food giants use premixed milk shakes that are dispensed into your cup.

Premixed or handmade, the quality of any milkshake can be easily defined by two qualities: flavor and consistency. A good milkshake will have both in balance, with the flavor riding the wave of creamy texture to present a pleasing whole. You can't fix a watery milkshake by dumping in more flavor, and you can't fix a bland milkshake by adding more fat.

In this article, we'll compare small (or "regular," if no small was offered) chocolate shakes from major fast-food chains. Nutritional info, where available, will be provided for each item, and letter grades will given along with tasting notes.

Wendy's: 410 calories, 11 grams fat, 35 mg cholesterol, 230 mg sodium, 69 grams carbs

Wendy's relied on its Frosty desserts for years to cover both the ice cream and milkshake bases. Recently, it's begun selling "Frosty shakes," and based on the taste of the one in this test, some further tweaking is in order. The consistency was watery, and the flavor was actually more reminiscent of coffee than chocolate, with a bitter aftertaste. Final grade: D.

Arby's: 507 calories, 13 grams fat, 34 mg cholesterol, 357 mg sodium, 84 grams carbs

Arby's is famous for its jamocha shakes, but the chocolate wouldn't disappoint, either. The flavor was rich and layered. The texture was a bit icy, with some crunching on the first few sips. Final grade: B

McDonald's: 440 calories, 10 grams fat, 40 mg cholesterol, 190 mg sodium, 76 grams carbs

McDonald's advertises its shakes as being "triple thick," but while this one was tasty, its consistency was more like a very thick eggnog than a good shake. From the first sip, a straw was all that was needed to consume it at a fairly good clip. The chocolate flavor was good, but not great. Final grade: C.

Jack In The Box: (16 ounces, larger than most) 750 calories, 36 grams fat, 115 mg cholesterol, 280 mg sodium, 95 grams carbs

JIB advertises "real ice cream" shakes, and the shakes are actually mixed in a way resembling the original. The extra effort shows. The texture was near-perfect, and the chocolate flavor stayed just this side of being too strong. You'll definitely need the spoon! Final grade: A.

Sonic: 540 calories, 16 grams fat, 60 mg cholesterol, 270 mg sodium, 89 grams carbs

While Sonic's menu is loaded with great food, this chocolate shake didn't quite fit with the rest. The consistency was very icy, and the chocolate flavor was very light. Even after melting a bit, which often lets flavors bloom a bit more, the taste only improved marginally. Final grade: D+.

Burger King: 470 calories, 14 grams fat, 55 mg cholesterol, 320 mg sodium, 75 grams carbs.

This shake had the strongest chocolate flavor of any in the test. If you've ever taken a shot of Hershey's syrup straight from the bottle -- admit it, you have -- you'll have a good idea what this shake is like. The consistency, however, was another matter, being a bit oily and not completely pleasant on the tongue. Final grade: B-.

Chick-Fil-A: (18.25 ounces) 760 calories, 28 grams fat, 95 mg cholesterol, 520 mg sodium, 113 grams carbs

You can't get one of these on Sunday, since all Chick-Fil-As close that day. But any other day of the week, as the song says, is fine. This shake will take you back to the days of drugstore soda counters, with a guy in a white paper hat mixing your drink to order. It's that good. The chocolate flavor and the creamy texture dance together perfectly, and it's a safe bet you'll like it so much you'll never get to the point where your straw comes into play. Final grade: A+.