The ease of use, speed to pay people who owe you money or have outstanding invoices that need payment is great compared with other services I've used in past years (Paypal).
It's easy for me as an owner/operator not having access at all times but they are working hard every day trying new things so it will get better over time - which always helps when dealing wtih customers needing immediate service!! Nothing really- just make sure your credit card has no issues before using this system otherwise there could be delays getting paid by someone else if their bank does issue them one. Easy way around any problems from another party such us PayPal where funds can sometimes take longer than expected due too slow transaction speeds between banks etc..