Just don't do the reverse camera at an authorised dealer, they said something like 10k for it? Someone must've gotten something wrong somewhere, it's 330 sterling on uk site, so no way it'll add up to that much.
HUD is standard. Sunroof is no loss, hardly ever use it and it removes the possibility of clogged drainage holes making a mess of things. Sport seats are pretty much basic standard seats with a bit more bolstering, as far as I can tell. Nothing special. Wheels are horrendous, I think the M5/M6 secondhand 19"s will be very much in demand. Proper authorised dealer bodykit update is like 17k just for exterior. You don't get the very nice thick M wheel with it tho. Overall the M spec looks way better than the regular ones, and black screen is nice.