I tow a KZ Sportsmen 242SBH which is 6000lbs GVWR and 24ft with a 2007 Envoy SLT that's equipped with a Reese dual cam system (properly setup). I will admit that the ride can be uncomfortable at times due to the short wheelbase.
Due to the limitations of the vehicle we only do local trips(1-2 hours max) that have no steep hills or mountains and it works great. On the highway I keep it under 55mph as that seems to give the best results (no push/pull and minimal sway when trucks pass).
The I-6 has plenty of power behind it, but you won't be climbing any mountains. If you do choose to tow with your trailblazer invest in a good WDH, brake controller, suspension, tires, and a transmission cooler.
@Salty Dog - Good to know I'm not the only one with electrical hell
I tell ya, after all the research I've been doing the past month, it's very hard to find the quad bunk or 3 bunk style bunkhouse you are referring to that will be under 31-32ft. Most of them that I've come across are 33-33' ft. And it totally bums me out, lol. I've found lots and lots of great twin over double "bunk house" style floor plans in the 28' range, but that's about it.
Have you looked at the KZ Spree 240BHS?
@crbii - Checkout the KZ models. We recently purchased a KZ Sportsmen 242SBH and love it.