Believe what you want, MB guys seem to have lots of problems modifying their cars to yield decent results, numbers, 1/4 mile times etc.. Keep in mind TVT never posted any track times, dyno graphs etc backing up the injectors and other mods. I have all the bolton stuff on my car and ran a stock number at the track. Am I satisfied with my car's performance - no. I am at the point where I am understanding that you will not make decent power whatsoever with this car without being able to access the tune. Save your money for the real stuff (turbo, standalone or piggyback etc..) and by the time you have enough there should be some options out there.