One of my friends had a 1st gen Colorado, the rare 4 cyl 5 speed regular cab short box model, and he didn't even really take it off road, and wore out the tie rod ends, ball joints, and wheel bearings prematurely. The front suspension also developed cracks around the area where the torsion bar fixes into the a-arm. Comparing that to my previous 2004 Tacoma, which took a heck of a beating and never complained, I would say they are an inferior design. One advantage a Tracker has over a Colorado is the coil sprung suspension on all 4 corners will yield more flex than a torsion bar design, and also the Colorado rear leaf springs are slung underneath the axle so you lose quite a bit of clearance compared to a coil which sits on top of the axle, or a sprung-over leaf ie: Tacoma. If you're a fabricator maybe you could find a Colorado for significantly cheaper than a similar aged Tacoma, swap a solid front axle into it, and do a spring-over-axle on the rear, and you'd have a pretty decent rig. The only thing you'd still be missing would be the option to run a manual transmission on a 4-door...but you do have the 5.3L V8 as an option so I guess that makes it even.