I know a 50/50 mix of water meth is most often recommended and that a 50/50 Isopropyl alcohol (IPA) water mix seems to be ok but would there be any harm in using 90/10 IPA/water or straight 100% IPA?
I have used straight methanol at 100% many times without any issues. I am not concerned by the fire risk.

I'm really wondering about components being damaged. IPA destroys nylon.