My P365 has been riding my sweaty back for almost 5 months now, and still looks new once I wipe the dew off of it
Do be cognizant of the fact that there is only one model with a safety other than your trigger finger... the P365, P365 SAS, and P365XL all are no-manual-safety versions.
It's rumored that at some point, SIG is going to sell the grip modules and all the parts required to mod your gun to a manual safety, but that day has not yet arrived. You can, however, already get the SAS slide assembly, which is F'n sweet IMO. 365 is my favorite small handgun, quite a departure from even my HK USP Compact 45 in size and weight.