I use their debit card and make purchase for what I have available.
Occasionally, I have transferred money to/from my PayPal account. It is very easy and the transfer usually occurs within 2-3 days. This helps if you overdraw a bank account too.
And the money is available at least as soon as you have been notified you were paid. I like it very much and wish all my Mystery Shop Co. used this for payment.
You can use their debit card just like any debit card, either debit/credit. If you need cash immediately, it will cost you from an ATM and the only hitch is you have to request your funds from your checking account even though you do not have a checking account per say. I know because I tried from a credit card and I had to contact PayPal.