I have an M5 Comp built in Oct. 2019. Bought it new in February 2020 (good month, year
). Now I have 125K KM (~78K Miles). I also did a stage 1 + OPF Delete at 100K KM (62K miles). It still runs like in day one, and I used it properly: daily driver, track days, burnouts, drifts, commuting, long-drive roadtrips.
I had absolutely no issue with it, I have changed only tyres (A LOT!), brakes, and the regular maintenance (filters, oil, etc). I'm always warming it up before sending it, and also, I'm cooling it before shutting it down.
So don't worry about high mileage, if it had good maintenance, it will last a lot.
Cheers.