its by far the toughest savage out there. the drivetrain parts are the strongest they make and it has the bulletproof diffs from the factory, which is the only flaw I've found on the X4.6 (diffs keep blowing on the 4.6).
what I've found is, it will destroy itself if you run 3s lipos. the truck is capable of 3 standing backflips but if you dont land it, it will break itself. I've bent the dogbone from the diff to the wheel and broke the axle in half just from a flip.
also, the motor on mine manages to turn in the mounting plate which jams the wires up against the speed control. on a backflip it knocked one of the motor wires out of the speed control and bent it so it wouldnt stay in. i used a small piece of aluminum foil and it now is tighter than the other ones.
from what i can tell, it will stay stock, probably forever. knock on wood on the X and Flux all the plastic parts are tough, no issues there... The two biggest issues I've fought though are
you pretty much have to red loktite the pinion gear set screw and the slipper clutch nut. it backs the slipper off no matter how tight you get it and then the spur gear ends up at over 200 degrees and you can smell it
