So, I've got the extended warranty and don't have buyer's remorse. I have a 3" lift, winch, and other modifications and it's quite obvious that I wheel the Jeep (banged up bumper, took some recent body damage, cross member has be "re-shaped" along with the gas tank skid, etc.) and my dealership's service department hasn't balked at covering an already LONG list of warranty repairs. Just going off of memory here, but with 31,000 miles on a 2013 they've covered:
Water Pump Replacement (Twice)
Input Shaft Bearings
Throwout Bearings
Shifter Assembly
Front Inner Axle Seals
Draglink
Software Updates
Heated Mirror Recall
Passenger-Side Heated Seat TSB
Some of those aren't really relevant to having modifications and I probably missed a few things, but my belabored point is that I'm glad I've got the extended warranty if I've had this many issues on a brand new vehicle and the service department is willing to take care of them.