Do the tour and everything if you want, but I think that the real atmosphere is much more important. Go to the library with a cup of coffee, check out the athletic center, sit on a bench on a quad when classes change. Can you see yourself there for (at least) four years? Often schools within a tier have negligible differences in terms of academic quality unless you are selecting a school specifically for it's strength in a particular department. It's much more important to find something that clicks with you. So anyway, long answer to a short question, but my answer is yes, if you can, definitely visit.