I bought one of the original Yoobao iPad 2 cases. It was fairly odorous to say the least but I threw it out on the deck for a couple of days and let the sun beat down on it. Now there is barely a smell with it at all.
The sleep function worked fine and also didn't cause the sleep problem when folded over. I love this case. It adds the least amount of weight to the iPad 2 and is very snug fitting. The problem with it was that the front cover didn't close tightly enough. As I carry my iPad 2 around in my work rucksack, I needed a way to keep the front cover closed.
As you can see from the images, I got a piece of elasticated fabric stuff (not sure what it is called) and sewed it into the case. Couldn't quite get the right colour thread but it looks OK to me. Now when I need to close the cover tightly I just loop the elastic band round the back.
I'm sure the Yoobao guys could make a version 3 of the case this way using the right colour elastic stuff for the red, brown and black cases. Obviously, if my case had been black you would not even notice the black elastic stuff. Actually it doesn't even have to be as wide as the stuff I used.