Well, I did join.  Their payment system is kind of a pain, I must say.  You can't charge part of an order to your voucher and pay the rest via credit card or PayPal.  If you want to use the voucher, you have to transfer money to your Cornucopia3D account to make up any difference.  And you can only transfer money in $10 increments.  Wish they'd do it like DAZ and Rosity do, and let you just charge the balance due.