I want to use them; but they can't take $US without a US bank account (we have a $US UK based bank account) or do Amex yet. Hopefully soon.
I spoke to them at their hack day in London at the beginning of April, and they said they expected to solve this in 1-3 months. So hopefully within the next 6 weeks if we're optimistic!
Hopefully something as 'simple' as USD charges getting sent to my GBP account, taking a forex hit along the way. I'd rather that than the red tape of setting up a US account.
GBP, USD, and EUR are a minimum, imo. Been doing that elsewhere since the 1990s. That's not meant to be snarky, simply factual.