With godaddy, if for any reason you decide not to renew your reseller account, your customers will become godaddy customers.
With enom, you can choose between using the api, or using a premade shop, managed by enom, credit card processing made by enom with big processing fees, 0.95$ + 3%
So, if you pay 8.95$/domain and charge 9.95$ you would be losing money, the processing fee would be 1.25$.
Also you will pay 99$ for the PDQ
Check
http://www.enom.com/pdq/faq_pdq.asp
I recommend you to fund the account, you are making business, don't expect other to pay your investments. You'll end earning more.