I haven't had luck with a buy then switch though that's great information to know. I have tried the walk up at the station but they have made a mistake on my ticket one too many times for me to do that. Or the agent is busy (understandably so) so they suggested I call in advance. Now I call in advance, lock in the price, and have them hold the reservation for a week. Using that method I've been at 100%.

I had about 9 E-Vouchers so I just called Amtrak to get all the voucher numbers as some didn't have emails that came with them. I just presented the numbers written down to the ticket agent at the station to make his/her life easier. Some agents know how to enter multiple vouchers and some have to call the help desk but at the end of the day the tickets were issued correctly. Can't wait until this can be done online or by phone!