I think Apple's Silicone Case is really nice, and stays clean. Very expensive however.
If you didn't need a keyboard nor a Pencil and liked Apple's Smart Cases? I bought a "clone/counterfeit" off AliExpress:
http://www.aliexpress.com/item/nice...pple-ipad-pro-case-9-7-cover/32650443102.html
Works very well actually, and for AUD$16 (around USD$13) delivered to Australia in around a week or so, I'm pretty happy with mine. Holes in the right places and magnets work properly. Feels pretty decent enough. I'd most likely purchase another colour later.
I decided to take a punt on them as they seemed to make the effort in highlighting the different versions: