Bottom line is that the upgrades to the 8,600 RPM tune and a smaller pulley were worth only 5-10 HP and probably aren't worth it to most since it voids the ESS warranty. I like the flexibility of the tune and typically try to shift around 8,300 to 8,400 RPM at the roll-on events which gives me some room for error to prevent hitting fuel-cut off which completely botches any acceleration run. Another reason for keeping the revs at 8,400 is that it starts getting a little lean at the very top which means I'm running at the limit of the fueling capacity.
Daily: 2013 e92 M3 MW FR DCT ZCP / ESS VT2 650 S/C, MRF mid/Akra slip, ST BBK
Track/Airstrip: 2011 997.2 Turbo S PDK / GIAC tuned / Ohlins coils+LCAs+endlinks setup by BBI Autosport
Beater: 2013 X5 3.5sport