I'll put in my two cents. I drove one as a DD and wheeler for the past seven years, a 92 2wd ext cab 2.3L 5spd. The travel with stock TTB is decent for what it is. If you're buying one, plan on reinforcing the coil buckets. They are made of cheap steel and their design allows dirt/salt/water to collect and rot them out. I lost my passenger side coil bucket just driving over a railroad track in downtown Bay City. Also, they tend to go through ball joints and wheel bearings. The bottom of the radiator core supports rust away, leaving the radiator floating. They are pretty much impossible to keep aligned. Check the radius arm bushings, they tend to rot out and cause more alignment problems. Check the frame for rot, mine rusted next to the gas tank and carrier bearing crossmember. The rear spring shackles rust out and will probably need replacing. The cab mounts tend to rust away, replace them before doing any jumping. The A4LD automatics are terribly weak. The M5OD 5spds are good, but check the shift rail plugs, they tend to leak slowly and overtime can lead to oil starvation.
For a budget dune toy, a 2wd ranger is a good choice. I did a fair amount of jumping in mine, especially right before I scrapped it, and they do well. Find one with minimal rust to start your build and you'll be all set.
What engine are you planning to use?