payfirma looks OK, but they charge many overhead fees to start (i.e startup fee $230, monthly fee $30) while their swipe fee is 1.99-2.99% + 25c. I wonder what is the criteria that differ the % from 1.99 - 2.99%?

paypal and stripe do not charge overhead, but a higher %. They both charge 2.9% + 30c per swipe. I like this as they charge flat fee.

I think for a web startup, it's best to take no overhead fee until business is established. If I have to pay payfirma 2.99% + 25c per swipe, it would be good to go stripe or paypal.

Has anyone use stripe? Any good/bad experience? How's their dev support for API integration support?

Thanks.