I have always been conscious of the regional American accents, because I am from originally from Minnesota, and even when I moved one state away to Wisconsin, I still got teased for my 'out' and 'about's!!
What I have been interested in and mildly impressed with are the British people that have picked up on my American regional accent. I lived in the DC area for 14 years, and I have had 3 Brits tell me I don't sound like I am from DC, and one asked me if I was from Canada. They must have refined ears
I can barely distinguish English from Scottish from Irish from Whelsh, and they're different countries!