T100's are quite the bastard child of Toyota...that is why I like them
Expect near zero aftermarket support in terms of bumpers, armor, etc. since not enough exist to create a market for them. I think TJM was the only company to offer a decent off the shelf bumper, good luck finding one in stock. I think for a wheeler, you probably want to have decent fab skills if you want any of these items, or just be willing to pay for custom. The good news is that a 4wd T100 has the same frame dimensions as an 86' to 95' Yota, just slightly wider. Rear axle is different (Taco style diff) and the leafs are different IIRC. For the most part everything interchanges frame wise. Note that for what it is, the suspension has all the great aspects of the IFS yota of its day, rebuildable bearings, ability to add locking hubs, etc.
Powertrain, I agree...stick out for a 5VZ. They are far superior and you have lots of room in a T100 engine bay for all the goodies if you want an extra battery or OBA. I would avoid the RZ engine, even though its one of the best engines ever made it is just too small in this application. Absolutely avoid the 3VZ unless you plan on doing an engine swap. You can get one blown up for a song but the 3.0 is probably the worst thing ever made.
The T100 is a great mix of solid Toyota dependability, slightly roomier dimensions so you aren't banging your head on the side glass while wheeling, yet small enough to fit anywhere the mini trucks go.
