This is a great product for the UK. Sadly, unless they get acquired quickly, they'll get destroyed by fraud. The Direct Debit Guarantee means that as the account-holder, I can tell the bank to give me my money back immediately, with no reason. So a fraudster will make some charges, run away with the money and GoCardless will be left holding the full liability.

This is one of the reasons that it's so painful to be allowed to process Direct Debit transactions in the UK.