I’m a month in on the NP3 and had it pre-release on 11 JUL. As far as the case is concerned, it does seem to possess a static charge that collected dust particles.
Honestly, I couldn’t mind less and remove the phone every few days and wipe it down (usually with my shirt but sometimes in the lab and with 70% EtOH).
I shocked at the looks of the Arc, it’s just not my thing, i.e. shockingly ugly. I’m tempted to go careless and this phone is shockingly good looking but it will get scratched to shit with my lifestyle (in bags, on bikes, in the gym, two kids, various lab environments), so I’ll keep the TPU until my kids break the rear glass cover.