I think it just really depends on the school. I applied to five schools (Masters programs) and got into two of them. I was similiar to you, 4.0 GPA, a lot of research experience including presenting at conferences, strong statement and letters, but I had low GRE scores. Perhaps those scores are what kept me from getting in to those three schools, but it's possible that based on research interests, those schools just weren't a good fit. I don't really know. Like I said at the beginning, I think it just depends on the school and the program. Maybe when you're looking at schools to apply to, check and see if they have cut-off scores for the GRE.