I have the Bear Motion case, which is a well made leather folio-style model. It activates the sleep function similarly to others. It's not as easy to remove the iPad from it as other cases (there's a velcro band that wraps under the iPad on the spine side of the case. It has holes in all the right places to access iPad buttons, cameras, and the speaker.

What it doesn't do, though, is protect the corners of the iPad. The edges are protected for the most part, but the corners aren't. It hasn't proven to be a practical issue in the week or so I've used it, but I'm concerned I might bang the ipad into something hard, or drop it on a cement floor, and scar it. I might pick up one of those polyurethane snap-on backs for the iPad; I believe it will still fit in case with that attached.