I doubt you'll have any trouble using a credit card even you're not the primary person on the account. I know a guy used his wife's credit card to pay in a supermarket, the cashier took a look at the card and then at him, didn't say anything and process the transaction
I also know a guy used his girlfriend's credit card.
In your user profile, if you didn't say hide your birthday blah blah blah, your age will show up under your location in your every posts.
About your credit card stories. But I don't know if it would have worked in the PayPal site--anyway I have already done an e check
It seems my e check may be slower than my normal checks
Thank goodness I did say hide my birthday in my profile--who wants to see their age on every post