I finally strapped my 135i onto the dyno after fine-tuning the new single turbo setup and am thrilled with the results. I did a handful of pulls at various power levels and attached the logs below. This should give everyone a good idea of what a properly set-up 6266 can do from low boost to high boost on an N54.
Doc Race Single Turbo Kit: https://bit.ly/2RK5DRY
All pulls done in 4th gear (manual transmission). DynoJet with STD correction set at 5.