WPMU Membership PayPal Recurring Payment Questions

I have a few questions about Membership and PayPal recurring payments.

1) Is the only way to use recurring payments with PayPal to use PayPal Standard and force all users to create PayPal accounts in order to pay a subscription?

2) Was the Pro Payments addition ever applied? If so, how do I use it? (see this thread: https://premium.wpmudev.org/forums/topic/paypal-pro-not-apperaing-in-payment-gateways)

3) I need to charge tax for some users and not for others. Is there a way to do this with Membership / PayPal without setting up an entirely new subscription in Membership?

4) Most of the posts I've come across in this forum reference PayPal Express, but I do not see this in the latest version of Membership (3.5.1.5 as of 8/27). Are these two different?