I had a similar reaction when I visited. I was very impressed by the school, but at a loss for why people would think the research wasn't as strong. I think part of it is that there aren't as many labs as you'd find at other schools. However, that absolutely does not mean that the quality of the research is weak. For instance, as a completely arbitrary measure, Duke has just as many HHMI investigators as WashU and Penn. So there is definitely good research there. For me though, the bottom line is that I was impressed with the faculty I met with. I would say if you felt the same way, ignore the reviews, and use your gut. Don't let a website dictate your opinion of a school - even if it's a good one.