We plan to purchase the Roma Pass when we get to Rome. How can the discount be applied to the Borghese Gallery if you have to reserve a week in advance?
We reserved the Borghese over the phone a few weeks in advance and were not charged at the time of the reservation. When we arrived, we gave them our Roma Passes and we only had to pay the separate reservation fee.
Reserving online is easy, http://www.ticketeria.it/ticketeria/borghese-eng.asp#
Just pick your time slot and wait for the return emails confirming your reservation. Print out and bring with you. The website usually only lets you reserve about a month ahead of time, so you may have to check back frequently. It does take a couple days for the confirmation reply. It's worth the hassle (phoning or online) just to see Bernini's "Apollo and Daphne" - breathtaking.
Like the others have posted, you do not pay in advance for the ticket. The Borghese Gallery is my favorite museum. The reservation system prevent crowds - unlike the Vatican musuem!
We did not reserve until we got to Rome, and determined whcih day would be best for us.
Thanks all for the helpful info! This is my first trip to Europe--I just can't wait!