My biggest concern with the latter is that if you want a vault+token system to avoid the serious PCI DSS hassles, PayPal seems to keep changing its mind about what the different options are: every time I've looked for quite a few years now, it seems like there are always several different things that each do (a different) 50-75% of what we're looking for, without any way to get the degree of control you have with some of the other services.
It's not like we have weird, exotic requirements, but we do want the flexibility to do things like moving a customer from one plan to another if they upgrade/downgrade, or reducing their payments temporarily or permanently as a result of a promotional offer, without them having to effectively sign up again with the payment service every time. Do you have any related issues with your startup, and if so, would you mind saying a bit about how you handled them with the different payment services you use?