We did this for one of our startups but had major issues after the first month when it turned out that spreedly doesn't db the credit card cvv ('cause they're not allowed) and then paypal wouldn't let us bill without the cvv code. We've had numerous issues with paypal not letting us do some simple things just because they made a decision at some point that we were sketchy and shouldn't be allowed and they tell us they'll NEVER EVER change their mind.
That said, we still use paypal recurring billing on a few sites cause its just sooo easy to do, even if it is a bit user unfriendly.
And also, Paypal only allows transactions without CVV for US and Canadian accounts, so if you're in another country Paypal + Spreedly isn't an option for recurring billing. Took an hour on the phone with Paypal to find this out.
That said, we still use paypal recurring billing on a few sites cause its just sooo easy to do, even if it is a bit user unfriendly.