MADISON, Wis. -- Sheets can cost $100 a set, so you'd expect good quality. But Consumer Reports' recent tests show you may not get it.

If you've checked out sheets lately, you know there's an overwhelming abundance of choices: Egyptian cotton, pima cotton, cotton percale. Plus all the different thread counts 300, 350 even 600 and higher. What really matters? Consumer Reports found out by putting 19 sets of sheets to the test.

Testers used a special machine to measure how much force it took to tear the sheets. That's an important guide to how long sheets will last.

Another test took place in a darkened room. Trained panelists rated softness by running their hands over the sheets.

Testers also repeatedly washed the sheets. They said the linen sheets came out badly wrinkled, and a silk pillowcase shredded in the wash.

If you think the higher the thread-count the better the sheet, Consumer Reports found that wasn't necessarily the case. One set of sheets promised a super-high thread count at 1,200 threads per inch, but they actually have around 400. A microscopic analysis shows there were 1,200 individual plies, not threads.

"Two-hundred threads per inch is fine, 400 may be softer. But anything above that has no added benefit and will just cost more," said Kim Kleman of Consumer Reports. "Traditional cotton sheets are your best choice. They combine easy care, comfort and durability.

So what do you need to know when shopping for sheets? Consumer Reports said a good choice is the Sealy Best Fit Sateen sheets. They have spandex panels on the top and bottom which provide an exceptionally good fit, and the queen set costs $90.

Several of the sheet sets Consumer Reports tested were incomplete, or sheets and pillowcases were torn. Testers suggest opening the package to make sure the set is complete and in good condition.