For the most part your butt dyno can detect overboost, but there's no substitute for a boost gauge. I can't understand why BMW left this out.
Everytime I fill out the BMW after service survey, I comment on the lack of an engine oil dipstick and boost gauge. Maybe one day they will listen.
On my baseline dynos the tech wasn't able to engage sport mode with traction control off, but my numbers were consistent with everyone elses.
I'm heading to the dyno tomorrow to see if I gained anything from the Helix intake and Berk midpipes.