I had to take the piggyback off the car due to the fact the car was due for inspection I, an oil change and a new alarm module. All in all, I drove around with the X5 is stock mode for a few weeks. Immediately, it felt the car lacked a lot of power in all the gears. Today, I re-installed the piggyback. WOW, it's amazing what the difference is.

The engine just feel so much more responsive without the turbo lag! Over the last few months, I've never had a check engine light, and the fuel consumption wasn't really any higher. Overall, I'll have to give this mod a full 5 stars. To everyone that is on the fence, this is really good value for your money. The extra torque is very noticeable, and compared to modifying the M3 for power, $400 is a bargain to get 30 HP and 50 FT/LBs of torque