Just installed the Scangauge II and the iDrive.
The iDrive makes a massive difference for a car that has been incredibly sensitive on the throttle and therefore difficult to drive in city conditions.
The Scangauge II has shown that the Boost gauge in the pillar is massively inaccurate, by well over 50% at times, but I've only driven a few minutes with it so far.
I look forward to seeing how they go long term, with more experience driving with them in the future.
I just have to get the fault code fixed, which will happen on Tuesday, and then the next stages begin.