The 1M is a limited production car, so it's value will hold up. They've been dynoing around 330wHP- yes, that's at the wheel. I've seen them tracked hard in 110 degree heat without problems and it has all M3 suspension components. It's an impressive car, but not a true //M. Unfortunately, it gives insight into the future of //M cars.
Let me get this straight... You are swapping out parts designed by some of the top engineers in the world because some guys sponsored by a company told you it's "better??" But when you ask the same guy about tracking, "oh no, I have a kid now" or "I just detailed my car." or "i just got new tires."