Well being 25 and coming into the league from Europe isn't the same thing as coming into the league out of college. He's been playing against grown men over there. He's considered one of the best players in Europe, and apparently Vlade tried to get him last offseason but failed. He's very long at 6'6" with a 6'11" wingspan, and is considered a good athlete. Most scouts think that with the proper coaching, that defense could be one of his attributes. Remains to be seen of course, but with Joerger being a defensive minded coach, one has to believe he'll get the most out of him in that area.
I won't start worrying about his age until I find out if he's someone I want around for 10 years or not. I never did get this age thing, especially coming out of college. How long does the average player spend on one team. Lets say he's everything were looking for in a player, and he's only productive till he's 35 years old. That's ten years from when he enters the league. I may not even be alive then. So I'm not going to lose any sleep over it. To me, it's much ado about nothing.