I have travelled alot in the US. For the most part all my experiences have been good. The exception is whenever I goto a hockey game down there. If im wearing my flames jersey or they find out I'm from Canada, 9 times out of 10 it turns into "Canadians Suck!!". Not your team sucks. I can handle that. Cheer for your team. But the amount of slagging and even some physical abuse I have gotten is brutal.
My opinion- Americans arent much different from us in everyday situations, unless they are in a hockey arena.