Mavic CrossMax SLR 2010 for xc-am training? (need help)

So i have a friend of mine here that he is a professional rider and he has many expensive components that he doesnt need them anymore and he's selling them..I was looking for a wheelset around 300euro(i am from greece) and he said to me that he is selling the crossmax for 450..They are not used as i 've seen them but i worry about their durability..We are talking about 1420gr and a superb-looking xc racing wheelset..So should i spend some more and take them or to go for a Mavic Crosstrail 2011 in a price of 350? I am really confused cause i am not a racer and i mostly do some "trainings" and some all mountain rides and i dont know if these wheels can handle it..(i read some reviews and mostly everyone say that this wheelset is their racing wheelset and not their every-day)