I have one. It's stable on a flat surface. Don't think you'd have a problem. The most outer edge of the cover fits into a channel near the magnetic bar so kind of "locks" into place when you have it folded into a stand. I have found the tablet angle is good.
I previously had more of a book-style padded cover for my iPad 2 (third party) so had my hesitations about buying this one but really wanted to have protection for the iPP when I received it. I can definitely say I'm happy with it. I have both the Apple silicone case and the cover. I think the cover is pretty lightweight. It snaps on quickly and stays on. The fit is good. It can also be removed quickly if you want. Sometimes when I'm laying in bed I just want to use the iPP without the cover and love how easily it can be detached when you need it to be. Otherwise it folds back and lays very flat so easy enough to hold in your hands with it on when you are in the portrait position.