Regarding reversals - here is the exert from our terms of service regarding this.
(e) User acknowledges and accepts that in case of any Transaction disputes, Paxum presumes that all Transactions by User are authorized by and are the liability of the User;
(g) User agrees that all Transactions initiated are final and not reversible;
(i) User agrees that any disputes that arise between Users are not the responsibility of Paxum;
That doesn't answer the biggest question (and your full terms don't seem to either): If I receive a payment through Paxum, under what circumstances, if any, will Paxum want me to give them back the money? In other words, what happens to the recipient(s) if the transaction into Paxum is reversed?
If Joe puts $1,500 into Paxum and then sends $1,500 to Jeff, and then Joe reverses the $1,500 payment to Paxum (claiming fraud or whatever), is that considered one of the "disputes that arise between Users" that Paxum takes no responsibility for? Or does Jeff keep the money and the dispute is between Joe and Paxum (since Joe breached rule 'e' above)?
I get that you take greater authentication steps than Dwolla does and that there should therefore be less fraud. But the big question is still -- ultimately, if there is fraud or alleged fraud (and no wrongdoing on the part of the recipient), who eats the cost?