I think he's still learning the NBA game and thats why he's not starting yet. Will he be as good against starters? Who knows, but you can tell he has a good feel for the game. He's tough and doesn't mind contact, actually looks for it!
I like to see them use him a little more in the offense to see what he can do. If he can pick and pop like KG did that would be a huge pick up. This guy sets some nasty screen, guys run into him and look dazed for a second. Its awesome!
Also the thing about most foreign players is that they are usually fundamentally sound, which will always give an advantage in this league, especially with bigs.