I have a 2000 LX version, and prior to that I had a 2007 Tundra with the 5.7L V8. Compared to that the cruiser seems underpowered. It seems like a large V6 vs. a V8. Keep in mind a few things though. It is all wheel drive, or 4WD. There is some loss related to that. It is built for reliability. I remember reading about a 2007 tundra hitting a million miles, and another from overseas that hit the million kilometer mark. Both trucks were taken from the owners by Toyota, and the owner received a new truck in return (with their permission of course). Then there was the teardown, on them and the ensuing marketing from that. I used that for justification to buy the Tundra with around 140k miles. While re-reading the same article later on when researching the 4.7L I realized that the million mile and million kilometer tundras both had the 4.7 in them. My understanding is that the 100 series 4.7l are built to hit a higher reliability spec than the standard versions they put in those million M/KM trucks.
The wheels are built so that they can hit a curb at 45MPH without failing. The ring and pinion in the rear are much larger than the ones in the new, higher output FJs that have recently been discontinued. If you get the Lexus version, there is even another 80 pounds of sound deadening over the Toyota version.
Finally, if you do happen to run the engine in the ground, and get tired of the poor fuel mileage, they might make a great candidate for one of those Cummins re-power swaps. Here is hoping that none of us have to make that choice, but it is out there none the less.