Believe me. It's very rare to find a mature Brit.

It's more so do with my age, and how I've been brought up. Though, it's also because I don't see a need in acting immature here.

All of the Brits I meet are pretty mature though.
Or it could be a view strengthened by stereotypes.

What stereotype is it that we behold that gives you that view?

''Ello good chap''
''Great day isn't it''
And tea.

I see what you mean :P
Though, *cough* that's totally only the English who speak like that, however, tea is amazing. ;)

I tried it and it is.

Milk and two sugars please.