The Recurly gateway is already included with the normal Recurly costs.
Zero out the gateway numbers in the calculator there and you will see the difference. http://expletiveinserted.com/recurring-payment-cost-calculat...
Granted, Stripe avoids the paperwork and business requirements for getting a merchant account. However, I already had most of those requirements ticked (you need them anyways if you intend to operate aboveboard), and I want all the subscription management features Recurly provides.
Further, the Recurly gateway includes credit card portability (Braintree is the only other company I know of that supports this). http://www.portabilitystandard.org/
EDIT: Removed incorrect merchant account fees.