I wouldnt bother investing in ProPay.

If you are going to invest in a merchant account at lease spend the time getting one thats worth while and going to get the job done right the first time.

I'm currently talking to a potential client of mine that is looking in exchanging site design services for a free merchant account.

It would be authorize.net. he would cover the app fee and the inital setup and I would be in charge of paying the $20 service fee.

Im getting a nice deal on 24cents transaction + 2.1%. Which is really good for a ISP.