Not bad at all for a protective case. Used for a couple of months now for S3 mini.
Tricky to put phone into case but even trickier to get the thing out! Typically one ends up accidentally removing the back cover of the phone bc of trying to ease off the protective (rubber/plastic) case, but this is probably better than the opposite of having too loose a case. Case actually composed of 2 parts - rubber flexible inner and hard rubber/plastic outer. Allegedly this provides the best protection if dropped etc.
Holes are accurately located and the two side buttons have special areas that you press through to activate the buttons. You need quite a strong press (grip?) to do this though, but again maybe this is a positive, so that they're not activated accidentally.
Have dropped phone (in case) a couple of times and so far, no damage. Impossible to say how effective it'll be if drop from height onto concrete & so on, & I'm sorry, but I'm not prepared to test it for the purposes of this review!
Sufficiently smooth to allow relatively easy placement into/extraction from my trouser pocket as well as being not very obtrusive above screen (abt 1mm lip).
Would be 5 stars but for the price - I paid around £21 + postage in early March '13, which compared to this case for other phone models, is certainly more.
UPDATE - 19th July 2013
Okay - so now I've tested it after dropping the phone onto a concrete path. It was an accident, but given that it happened and the phone appears intact, I thought I'd use this opportunity to update this review in a more positive light!
Hope this helps!