This is a problem I had with my SRT-4. I found out that it never scratched the bottom of the bummer, it was only the plastic/rubber diffuser. This is why I am not going to lower my xfire. I don't see it being very practical for my daily driver for the next 5 years. Maybe after I graduate and purchase another car this will be a good mod.

If you lower your xfire you will scrape it on something at one point or another.