Can you please confirm that card details are not stored anywhere within JoomDonation/Joomla i.e. they are only input at the payment providers site. I would be using Worldpay and PayPal.
Yes. That's right. Credit card information will only be stored on payment gateway, not the Joomla site. For WorldPay and PayPal, users will enter credit card information directly on the payment gateway, not on the Joomla site, so you do not have to worry about it