I researched to find the best deals for a weekend trip with two friends to Boston and this was a must-get. We got the two day pass since we were going to be there for 3.5 days and wanted to have a day to just wander around with no agenda.
I lost my pass during the first day and was convinced that I was doomed to missing out on all the rest of the fun but my friends insisted that I ask if there was anything to remedy the situation. The people at the GoBoston kiosk were not helpful but said that I call the support line on the back of the card (which I did not have but my friends fortunately still had theirs.) The lady was so helpful and emailed me a copy of the voucher. She was able to do that based off of the numbering of the pass of my friend, who purchased hers right after mine.
Come to find out, she sent the voucher for my other friend, which we found out at the Prudential Building overlook, where you are allowed the redeem only once. The lady I talked to after that apologized for the mistake and sent me the correct voucher.
All-in-all, it was a great value for the money and they actually CARE about your getting to use the card and don't have a "Tough, sorry about your luck that you lost it, not our problem" attitude. :)