My business partner has an H2. He likes it fine. He got headers and exhaust added to it.

After he did that, I tuned it for him (using EFI live - OK I had it tuned, then tweaked it a bit).

After 3 years, he's hot now for a Range Rover Supercharged. He's never had any problems with the Hummer, other than he likes a new car every couple of years, and it's about that time.