The stand mixer to buy once.

The Classic is the simplest KitchenAid stand mixer: metal construction, a 4.5 quart stainless bowl, 10 speeds and the tilt-head design. KitchenAid says the bowl holds about 8 dozen cookies in a batch. It comes with a coated flat beater, coated dough hook and 6-wire whip, and it takes every attachment the more expensive models do.

For a small household that bakes cakes, cookies and the occasional loaf, it does the job for a long time. The bowl has no handle, which is the difference you notice first.

Skip it if you bake bread often or double recipes. The price gap to the Artisan is small, and the extra half quart is worth having.

The Artisan is the KitchenAid most people picture: tilt-head, 5 quart stainless bowl with a handle, 10 speeds and a pouring shield. Every Artisan uses the same 325 watt motor, rated for recipes with up to about 9 cups of flour, and the color is the only real difference between versions.

It handles cookies, cakes, meringues and one or two loaves of bread at a time. The attachment hub on the front takes pasta rollers, grinders, slicers and the rest, and KitchenAid covers the machine with a one-year replacement warranty.

Skip it if you knead stiff whole wheat or bagel dough every week. A tilt-head machine can strain and rock under that load; the bowl-lift models and the Bosch are built for it.

The KSM55 is one of KitchenAid's redesigned bowl-lift machines. The bowl locks at three points and a lever raises it to the beater, rather than the head tilting down, which keeps the machine steadier with heavy dough. KitchenAid says it delivers twice the power in the bowl of the Artisan, measured at peak above speed 2.

It has 11 speeds, including a half speed for folding in berries or egg whites, and KitchenAid says the 5.5 quart bowl kneads over 7 pounds of bread dough or mixes 11 dozen cookies. It includes a coated flat beater, coated dough hook and 6-wire whip.

Skip it if your kitchen has low upper cabinets, and measure first. Bowl-lift machines are taller than tilt-heads, and scraping down the bowl takes a little more reaching.

The Bosch Universal Plus looks nothing like a KitchenAid. The 500 watt motor sits under the bowl and drives it through a belt, with a dough hook rising from the center. The 6.5 quart bowl is BPA-free plastic with a handle, and it is dishwasher safe. Bosch says it kneads up to 15 pounds of whole grain dough, about 14 loaves, or 34 dozen cookies.

Because the drive comes from below, the top of the bowl is open for adding ingredients as it runs. The whole machine weighs about 13 pounds, light enough to come out of the cupboard easily. NutriMill, the US distributor, covers the motor and transmission for three years.

Skip it if you mostly make cakes and small batches, or if you want a mixer to leave out as a centerpiece. The plastic bowl and utilitarian look are not for display, and the attachments do not fit a KitchenAid hub.