Getting quality numbers for a tune is indeed a problem. I personally have the ESS tune but have seen no dyno numbers that show a before and after. The few I think I saw of AA showed no gains. I'd love to see some solid proof of the shark, or back-to-back proof of any tune for that matter.
2003 BMW 330i ZHP
BMW Performance Intake and SSK - Headers - Magnaflow - ESS Tuning
Turner Motorsports Pullies and Reinforcements - H&R Spacers - StopTech