i own a H3T w/ the 5 banger. you get bad gas mileage regardless so you might as well get the extra power. im not sure why GM put a 5cyl. in a hummer? regardless i love my truck and wouldnt drive anything else.

 

Definitely, get the v8. I spent alot of time trying to find a clean/low miles/reasonably priced H3, however, I should have spent more time finding a V8. The I5 has decent power, however I want more, and if my I5 ever fails, I will replace it with a V8. GL