Can't really say which I like better. Ultimately, I like living in Europe.
Speaking of "America", one should also make a difference between the US and Canada.
Personally, I find Canada more pleasant, maybe because it has more European influence (for example the French, however one thinks about Québec, but some places are as well more "British" than "American": Ottawa).
I also like the New England states.
However, coming back from the US or Canada, I find that Europeans could be a bit more polite.
On the other hand, maybe that is what makes the European charm?
We are a headstrong, ever critizing, sometimes downright cantankerous bunch, much more than the Americans. But I think that is just fine.