I'm seeking a Wordpress plugin for course registration that has ecommerce functionality built in (ie: must support either Authorize.net or USA ePay).
The plugin should have inventory management features built-in (we need to keep track of how many "seats" have been sold for a course vs. how many seats are actually available) -- and it's important that the ecommerce functionality NOT redirect the user to any other sites/domains. We want to keep the customer on the same site/domain at all times throughout the checkout process.
I am already aware of the "Event Espresso" plugin, .. and am considering getting the Premium edition. However, .. I am interested in other possible solutions, .. paid or otherwise. In particular -- I am interested in solutions that are regarded as being even better than Event Espresso.