So just an interesting "real life with aftermarket parts" note:
The RDSport bar uses some kind of poly bushings instead of a bushing/bearing hybrid like the OEM setup. The bar started to make some noise after about 2k miles, but only when both wheels were moving in concert, so it was rare, because that's the only time the bar really moves in the bushings to any great degree. I lubed the bushings before installing but they needed another squirt, so I got some of my trusty White Lightning lithium bike chain grease and hosed it down and all is well. Probably needs more frequent maintenance than the stock bits to stay quiet, no surprise there.
I put the bar on full stiff with putting the PS2's back on after our "winter" and it definitely makes the car understeer more at higher speeds (though like before the car is much more responsive to throttle adjustments) but it's ridiculous in transitions now, and the balance is still really good in 2nd gear, you can do all of your steering with the throttle but it's less likely to get into a huge power oversteer than with the stock bar.
Still no dampers. MCS is still developing a setup and I have not pulled the trigger yet on JRZ's because I don't particularly want to cannibalize my spare stock struts for their mounts, but the JRZ's are still an option. I have one other iron in the fire and it might end up being the way I go but it's unproven too. Blazing saddles...er...trails
I also did a little comparison against the main competitors in AS and the S2000 in BS. The M3 has a big power/weight advantage over all of them, and is about 8% behind everybody on tire/weight, middle of the road on width, and severely lacking in CG against everything but the 1M. I'm thinking this car belongs in the CS range based on performance potential on most courses, but at a fast open course it could be the car even in AS, though probably not even then with the 1M in the mix. FS looks like a bit of a stretch considering the width, CG, and IRS. But I'm still going to write the letter
Either way I'm going in with the assumption that if I can't get it done, it's a driver problem.
Also of note, the E9x M3 was recently classed in ASP. So no ESP not-otherwise-classed V8 sedan cherry picking anymore...