The rear is pretty tough if you installed hd axles. I've twisted my rear driveshaft without breaking anything. As for the front, you'll break or eat a front cv at some point...it's not a matter of if, but when...I've been running TT's front and rear for 3 years now, been just about everywhere and I've broken 4 front's cv's, 2 in the east on muddy terrian and 2 out west, one in Sedona and one in my backyard...carry a spare front cv and you'll be fine...
frank