The snapping tendancy sounds like an accelerated stall, and this tendancy is common with the scale aerobatic planes. They have thin tapered wings and are much more prone to tip stalling than are fun flys and sport planes. You need to fly it more like a pattern plane (i.e. larger, more gracefull manuevers) and don't try to use large elevator throws except during 3D type manuvers where you are flying in a stall anyway.

On the other hand, if the problem is really servere and you cannot even use enough elevator to fly the plane comfortably, you might look for a construction defect that would trigger an early tip stall - in particular wash-in on one of the wings (that is, uptwist at the tip). I had a wash-in problem on an Edge and the plane was a nightmare to fly until I got a new (straight) wing.

Good luck,
Greg