A few questions before spending the extra money to get the Paypal integration:
1) Will this integrate with Paypal Website Payments Standard and/or Pro?
2) Will we still get email notification as usual, plus the contents of the form saved in WordPress as usual?
3) This is the form we want to recreate using GF:
http://taurus.cnr.colostate.edu/projects/elc/
Basically it collects registrant info, provides an option to purchase a membership, and allows them to choose one or more programs to attend (if they choose to purchase a membership, a different set of program prices are shown conditionally). Is this doable? I've used GF before, but not with Paypal integration.