jangy

No proof but everyone knows I was not a believer in them until I was given a test mule. I did more than just test it. we attempted to reverse engineer it by comparing the output signal to the input. That is when we noticed that it keeps a steady minimal signal going. What else it is programmed to do, I dunno but for $300 you will not find a better mod to satisfy your dyno butt.

jangy

Double NO. You either misunderstood or are just wrong. It does plug in at the pedal, but it definitely effects the ECU. While no power gains have been claimed, I wouldn't be too sure about those 0 - 60 numbers. It all depends on when you start the clock. If you wanna start it when the wheels start turning, then maybe there is no difference. But, if you count from when any pedal is applied the Sprint Booster car will always jump out of the gates sooner.

jangy

Here is the deal. HP numbers from the manufacturers are nothing but marketing. They run zillions of runs and yet only claim the one that meets their needs. Perfect case in point was the kompressed E55. Because it was the only 500hp car for under $100K, MB understated the numbers so that their more expensive cars would hold water.
In this case, BMW is the one that actually devalued the 335i to keep the M3 and 5 series from losing sales. Also, the current class standard has been at 268hp since '06 and is just now getting bumped to 300hp by the BMW and G.

Now, for why MB doesn't just make their cars tuned from the get...The issue is that they need to be sure that their cars perform under some very adverse situations, where a modded car would simply not flourish. Things like gas quality, service intervals, etc. can dramaticaly effect the long run of a car and MB simply can't have the failure rate that even the top tuners have.

Hope that helps.