Unless you really like the Smart Cover, I would stay away and keep searching. This forum is excellent to see the different cases out there that others have already purchased and offered their reviews on. It's great to do the research on here and let others do all the purchases so you can limit yours. I prefer an all in one case with case back and cover attached so you don't have to even think about the cover coming unattached. For me the smart cover slipped around on me in the typing mode and that was a deal breaker.
With all that said, it truly is a matter of personal choice. My favorite case out there is the Griffin Intellicase. While it's my favorite, many others do not like this case. What I like about this case is it's slimness and light weight, material that is easy to clean, open bezel, many colors, cover that works perfectly with the sleep/awake feature and best of all perfect stable and secure stand function. Others prefer a leather case, more protection, and stands that have either the fold up covers or the cases that fit in the slots and/or rotate. For my use, which is mostly in my lap typing and reading or watching movies in bed, the Griffin gives me the best option.
