LSM - haha my dyno numbers are all straight out of the factory OEM BMW my friend
voltans4 - I've seen the new M5/M6 on Dyno Dynamics run dyno # from 480-490 rwhp max to be more accurate. It's all based on the dyno machine, temperature/weather, and how updated everyones software is as well.
As far as the BMS tune goes, keep in mind its still only just a "piggyback" unit there is no actual real ECU tune released just yet.
Anyone can be pulling different #'s based on each piggyback unit bc it's all based on how much you turn up the boost by optimizing it on the dyno rather than just doing a plug and play.
At the end of the day what matters most is safety on voiding warranty or blowing up our engines (or far worse).
I've driven my good friends Switzer Tuned M6 Coupe that is completely stock beat fully modded M5/M6's with the BMS Tune piggybacks just from upping his boost to 21.5 lbs. (Felt fast as HELL)