Gravity Forms eCommerce plugin?

Hello Sitepoint,

I have a client who takes donations. They use Wordpress, PayPal Pro, Gravity Forms and a product called PHPurchase. I have had no end to problems with browser compatibility and PHPurchase.

Can anyone make a recommendation for using an ecommerse plug-in for WP? It does not have to be compatible with GF.

They do not sell products or mange inventory, they simply accept donations.

Thanks