I'm no expert but I do have a comment on this;
I came from a subaru so Im familiar with BOV's, more importantly the need not to use them. BOV's really are pointless unless you're swapping out for larger turbos.
But more importantly, the were issues with cars (subarus) with BOVs (atmospheric, not recirculating) cause the car to run rich momentarily slightly hindering performance. No known aftermarket remapping ever solved this problem. Most of the kids that put these units on didn't really care about the performance just sound. I couldn't imagine doing this to this car (335i). With so many fancy sensors and an iffy HPFP, why risk it?
Just thought I could give a little comment based on what I've learned.