I have broke both bolts that hold the lower control arms, mid axle on my 2010 big boss. the One side broke at 550 miles the right side broke at 600. Pretty easy fix, even on the trail, If you have the bolt! From my talking with Hatcher pass polaris this bolt seems to break fairly often. My advice is change these bolts out every few hunderd miles and carry a spare with you in the field. Or at the very least carry a spare. Pay attention to those wheels. The first time it broke on me I couldnt see what was wrong till it was too late. Ended up bending the upper control arm.
Im thinking of seeing if I can find a grade 10.5.