The US is great for free speech as its constitutionally protected. However it is also very corrupt. Pros and cons.

There are a lot of advantages to constitutional monarchies in terms of stability. The monarchs do not actually have much power. I on balance prefer living in the UK and would not want to move to the US. There are pros and cons, and its culture and society (e.g. unarmed police) as well as politics and some if it is about personal circumstances (as someone who is obviously ethnic minority or foreign everywhere in the world I prefer a less racist society, for example).

I can yell "down with the King" or "down with the Prime Minister" pretty much anywhere. There are some restrictions on protest in a few places like Parliament square.