I just got back from the Rubicon. The only thing that I broke was a stock lower control arm. Once that broke, the upper on the same side got bent in a banana-like shape.
One of the guys had a welding rig for his 2 batteries. About 2 hours during lunch to prep and weld it, and we were back on the trail.
I did have front axle shafts, ball joints, u-joints (both axle and driveshaft), and a front unit bearing along as spares, but I did not need any of them.
If you still have stock control arms, bring a few spares along, especially lowers.
And have fun! It was a blast, and my favorite wheeling trip so far.