Valentin,

My Nexus has been good to me - reasonably! (It's my first chopper.) If I had it to do again, though, I'd probably look at a good 60, (the Raptor seems to be held in high regard).

One of my buddies at the field also flies a Nexus, and constantly has to recheck his tracking. (I've found at least one web site that lists this as an inherent problem with the Nexus.)

My Nexus developed some slop in the head, (after 1 1/2 gallons of fuel), that I managed to track down: the pitch lever pivot pin had worn the outer edges of the chassis hole it passes through. This allowed, at hover, abrupt changes in collective - which were a fun learning experience!

If you're new at helis, let me suggest that - whichever bird you decide on - the second-best training aid you can get is the CoPilot, IMHO. Correctly set, and calibrated, it won't interfere with your cyclic control while learning - but it could save you considerable expense!