Not sure what your timeframe is like, but:
Anything Beta is always scary, but it might be worth a call to see what their timeframe is like. The only reason I'm suggesting is that our experience with them has been very positive to date in terms of their API, flexibility and support.
Is Stripe available in the UK?
Additionally, if you’re creating a marketplace, store builder, invoicing system, or anything else that helps users get paid, you can use Stripe Connect to let your users accept credit cards instantly by having them connect their Stripe account.
We’re currently testing the next iteration of Stripe Connect in private beta. The new Stripe Connect gives you, among other things, the ability to transfer funds received from credit cards to third-party bank accounts in any country supported by Stripe, while fully owning the seller experience. Please contact us if you want to give it a go. We’re regularly inviting people who express interest as we continue polishing the beta.