The last 2 fill-ups were 28 and 29 MPG on the ratio of 85% freeway and 15% street. The magic 30mpg has not been attained as of yet, and I am wondering if a cruise to Vegas or Laughlin could get me that 30mpg since that would be pretty much 98% freeway driving. When I take that cruise, I will let you all know.

Overall, I am quite happy with the torque and HP increase. On the freeways, my XFIRE gets me around the clogs of cars with the greatest of ease. Accelerating onto the freeway is the same. Is the upgrade worth the $600, for me, yeah. In the long run, each one must make that decision according to their own wallet. One last thing, when I took my X-FIRE for my first oil change ( 5K ), the mechanic that drove my car ( and this is just on the lot ) exclaimed that my X-FIRE felt more power than the other XFIRE he had driven when he accelerated. Not knowing DAIMLER's stand on this upgrade, I told him there was no need for flattery since I would be bringing my XFIRE for servicing at this dealership since that was where I purchased it. He insisted he was not blowing smoke and felt my XFIRE had more pep than other XFIRES he has driven. I said "KOOL".

Still turning heads...