For anybody else with a slight interest...
I have signed up for a debit card account through them. That part was easy enough and took a few mins, plus a photo of my passport, and £20. The £20 is credited to the account, and also serves as an ID check- it comes from a bank account.
I am due to get paid some money in dollars which is the main reason for setting this up. I also travel a bit, and like to buy tools in dollars when I am in the USA. All round, it appears to be a good thing. Time will tell for me.