F85 Stage 2 - what else do you recommend?

[kevvygp]

I'm about to install VRSF catless pipes with the matching BM3 stage 2 software. Car has 60,000miles and no worries, pulls strong and smooth, currently running BM3 stage 1. As part of this tune I'm going to be servicing/replacing the transmission, transfer case, and of course engine oil, filters, and coolant etc to refresh those usual things (car is very well serviced). Will replace the turbo V bands and downpipe gaskets too of course. I run the car on 93 or 94 Octane (well that's what it says on the pump right?) all the time with around 8oz of Boostane most fills, with the occasional "cleaning run" (that's a whole other thread please let it go for now, it works for me). Plugs and coils were changed just a few weeks ago too (1 step colder) for the tune.

As part of the stage 2, just wondering if folks had suggestions for other items to consider replacing, checking, or upgrading (within reason) as part of the stage 2 upgrade. Generally speaking most people put on DPs, software, and off you go! I just figure while it's open and I'm working on her, what else might be good to service? Anyone know any benefits of high flow air filters? Mixed reviews there. BOV/diverter valve upgrades? Coolant hoses to check/replace? General weak points to look at? Wastegate rattle fix/replacement?

I know the S63TU2 seems pretty darn strong and many folks report upgrades over 700hpwith no issues for years, but I'd prefer to be cautious and take any advice from those who have done it before or have had issues. The BM3 stage 2 claims around 680hp which, regardless of accuracy, is where I will stop the madness Thanks!