I am an occasional tracker, so dropping a few hundred bucks on a bespoke kit for the OEM brakes would be perfect, and something you can drop in and drop out just for track days sounds when changing pads is even better! Much more preferable than spending several G's on a BBK that I don't need most of the time.
I think you need to provide the full kit to ensure consistency of fit and performance.
[this isn't going to be another E9X harness thing is it???