Alright, so I know ethylene glycol based coolants are a big no no since it's about as grippy as oil on the track, but what other types of coolant? Propylene glycol for example. And then what about water wetter.

I know the st George series says you can only run water in the radiator, but as far as I know, that's just to avoid getting any ethylene glycol on the track in the event of a spill.

I really just want to know if I can run water wetter in my cooling system in the st George series, because draining coolant is a pain and I strongly dislike the idea of running water 100% of the time.