I tried a 1$ transfer using a virtual payment card (I can obtain a one time card number on my bank site limited to a specific amount, this is usefull for online purchases). I could not link this card: "Card not supported".
Too bad, i really wanted to test their service with a spoofed mail after doing first transaction normally.
There is no way I'll be providing them my real card number.
Hint: they do not brag about being PCI DSS certified (not even compliant) that certainly means they are not.
They only say: "You’re safe with us. The privacy and security of your financial information is our top priority." which is not very reassuring to say the least.