If you have room for the PA120.3 and have the cash then go for it, it's the dogs danglers
If your G0 is getting hot, it's either concave, or your heatsink isn't seated properly. As a rule, they run pretty cool.
You could also save a fair chunk of cash and go with a high end air cooling setup like you mentioned. Both will perform well, obviously the watercooling will perform better, but it costs more. It also depends what kind of overclocks you are going for
