EVERYBODY OPENS cans.

Even the purest of cooks has probably cranked open a tin of devilled ham somewhere along the line. And most of us have experienced the instant gratification of the odd can of chicken noodle soup.

A good, solid, workable can opener is one of the mainstays of kitchen life. So we had an Opening. We bought six mechanical hand-held can openers whose prices ranged from about $1 to about $10, and we opened. The testers were male and female, from 18 to 80, non-cooks and good cooks. The openers we tested are widely available in hardware, department and kitchenware stores. They were judged on how easily they opened cans and how comfortable and convenient they were to operate. Many of them had bottle openers attached.

The openers were, in ascending price order: a 95-cent all-metal Ekco; a $1.69 Ekco, also all-metal but with longer handle; a $3.79 Swing-A-Way "Jr."; a $4.59 Swing-A-Way ("The first can opener in space"); a $5.09 Bonny with a wooden handle; and a $10.99 Ekco with plastic handle.

The $4.59 Swing-A-Way was the hands-down winner in every category. Testers described it as "sturdy," "reliable," "great," "excellent" and "the best!" What distinguishes this can opener from its slightly cheaper Swing-A-Way cousin (besides its being the first can opener in space) is a set of gears that drives the cutting blade forward. Because of the gears the cutting blade only has to cut and is relieved of having also to make forward progress on its own.

Other good qualities of this Swing-A-Way (model 407) include its relatively long turning handle, and its secure-feeling, plastic-covered gripping handles.

The favorite can opener was not the most expensive, but the cheapest was the least favorite. This can opener, the handle-less 95-cent Ekco "Miracle Roll," elicited patches of real hostility in a few of the testers. Most of them rated it the worst possible in ease of operation and comfort; one commented: "It's not worth using . . . ever!" Several testers said it was painful to use, and those who hadn't used it before had difficulty figuring out how to get it started.

This can opener, however, is one that has graced the drawers of many a kitchen, and I have talked to people who stand by it. Two of our testers noted that it would be good for camping because it is light and small and includes a bottle opener. But in general our testers, even the 80-year-old, were not swayed by sentimentality and gave this opener a rousing vote of thumbs-down.

Running a close second to the Swing-A-Way were the $10.99 Ekco and the cheaper Swing-A-Way "Jr." The Ekco, with plastic-covered handles and gear-driven cutter, is similar in design to the larger Swing-A-Way. In general it worked well, but there were two complaints. They were that it has no bottle opener and that it is stiff to turn.

The smaller, cheaper Swing-A-Way was found to be relatively uncomfortable and too light by a majority of testers. Two testers volunteered that for an extra 80 cents the heavier Swing-A-Way was much the better buy. Testers found the metal Ekco with long metal handles a good buy but relatively uncomfortable to use because the metal grips dug into their hands.

The next-to-least favorite was the Bonny, which is engineered differently from the others. Instead of being activated by squeezing the rim of the can between the blade and its turning wheel, this opener begins to work when you press down on the top of the can, then turn the handle, which is located on top of the blade instead of on the side. Although this opener was roundly disliked by our testers because of its "unnecessary complexity" and the fact that it had a tendency to slip, one left-handed tester noted that it is as easily used by a left-hander as a right-hander.

The left-hander still preferred the Swing-A-Way, however--agreeing with the other testers that the first can opener in space is best they could find on earth.