Membership Pro Signup form customisation?

Hi,
I'm doing some research for the best option for a plugin for a members site and the Membership Pro plugin definitely seems to do almost everything I need.

The one thing I can't find any mention of though is whether I can customise the form on the registration page or not? I need to be able collect more information about each member and either store it in additional custom fields or at the very least, email it to the site admin.

Ideally what would be awesome is if this could integrate with Gravity Forms so you could have the option to use a form created in Gravity forms for signup instead?

Thanks
Kirsty