Installed the Akropovic catless downpipes yesterday. Went for a first drive this morning and definitely an improvement in power coming on earlier.
The pops and snaps in Sport and Sport+ are now so loud that they've moved strongly into "annoying" territory. Now that I've got an impending check-engine-light and am motivated to tweak cold start, burbles, and exhaust flap behavior, I'm probably going to pull and mail out the DME for unlock.
Current garage: