I've played at M&M Paintball, Tsunami, Pro Paintball, Outdoor Cabin (when it was open) It's Paintball, POW Paintball, X-paintball and several others I can't think of at the moment.
GRC is in my opinion the best field around. I regularly drive 1.5 hours one way to get to GRC over going to some local fields that are less than 20 minutes away.
GRC has several field that are always changing. There is the hyerball field, the outdoor air ball field (sometime two of them), the woods field and the village. Beyond all of this, there is a HUGE indoor airball field that is different every time I play there. So no matter what the weather is like, it's always a great paintball day at GRC.
Some of the nice things about GRC are: real bathrooms, not porta-johns, 4500psi HPA fills, Co2 fills, an on-site proshop, on-location food and both indoor and outdoor field viewing area's for spectators.
GRC is my home field and as far as I am concerned the best field in most if not all of New York State.