[GammaZeta]

I've been reading a lot about M tunes recently and wanted to know if I am on the right track with my information.

Three tuners offer the...tune:

Active Autowerke for $499

Evolve for $679

ESS for $995

Now the ESS and Evolve involve sending the data file of your car to the tuning company? Whereas the AA is just an ECU insert?

Do people find they are worth the investment? I know it won't be a miracle tune that will make a stock Z4M a 400 hp beast, but it smooths out the power band and fixes some of the quirks.

Does one company focus on a specific more than another? I know with the AA it make the sport button ALWAYS on, which I am a little leery of. Does one company focus more on tunes with CAI and exhausts, while another is better for just a stock setup?

Since I run on 93 octane, does one tune favor that?

I had a Conforti Shark tune for my Z3M, and it was ok. It really was barely noticeable. Will the Z4M tune produce more of a difference?

Thanks!