I like mine, they are essentially worthless now and they just run. Problem is finding a clean one (interior wise) since they are popular broke family cars and they get thrashed now that the prices came down so much.
If you spring for a v8 model you lose a little fuel mileage but gain bigger front disks, bigger rear end, and a good amount of power reserve. They also don't seem to rust out nearly as bad as the 99-06 pickup and Tahoe/burnans.
It's the last full frame v8 rwd "truck based" vehicle you can get that isn't huge. I guess maybe a Dakota but they have the dreaded 4.7
I want to replace my Rainier simply because it's got 250k on it but parts are CHEAP and it's comfortable, pulls a car trailer, fits in a parking lot easy and overall the build quality is pretty good.
A envoy Denali or Rainier are good bets for v8 aluminum 5.3 or late trailblazers. Saab 9-7 also.
Only thing that sucks is the air bag suspension is flaky and the v8 is really to big for the chassis and they are tough to work on the sides for plugs or manifolds. Also front diffs are a bit funny being bolted to the pan but mine had been great so far. Front wheel bearing are like fuses and seem to go out religiously at 50k miles. The Rainer, bravada and saab got the annoying awd tcase you can't shift so if I got another one I'd go envoy since you can manually lock 4wd.
If I find a low miles late production envoy Denali cheap I might just 6l80e swap the 60e out and run one of those another 8 years. Problem is they ended production right when the 6 speed came out and the 60e definitely lacks the ease of towing (always jumping out of 4) you get with a 6 speed. The 08 Denali got the gen 4 LS so some brackets and driveshafts and wiring and they alegegedly fit nice.
I was lucky to find mine 4 years ago. It only had about 112k miles at the time, and was very clean both inside and out. I would guess it spent most of it's life as a second or third vehicle. It is also a 5.3 v8. For the Trailblazer the only way to get a v8 was either in the SS or as an option on the EXT. And I suspect that most of the EXT models had the 6, but I am not sure. I think the only model that never had a v8 was the Olds Bravada.