As a GM tech i can tell ya that with a improperly tuned dmax with a chip does some serious damage. I have seen it first hand. Make sure at least put a egt gauge in to mointor your exhaust temps. If you still have factory warranty you might lose it if the dealer finds out you had a power up device on it. Personally I'm strongly against power up devices but to each his own. I work on dmax's all day long and they are strong engine. Had a customer install a chip on a lly motor and burnt down two holes in the block. melted the tops of both pistons and scored the
the block. That little repair cost him his job with the company and he had to pay about 15,000 for a new motor plus labor. If you know how to use the chip wisely you might be safe.