Like so many other things at Amtrak, finding a complete and uniform answer regarding the 10 trip/45 day pass from anyone is nearly impossible.

These things I know for sure:

-they are not transferable (but I have never had my id checked). I'm quite sure you will not be able to use for two passengers riding simultaneously.

-You can use them on unreserved trains, and on SOME reserved trains. I have not found any info available to customers that explains which are the reserved train exceptions. After plenty of asking around (since the ticket itself says "valid on some unreserved trains, ask agent") a conductor aboard was able to give me an internal memo stating which reserved trains are ok between what stations. I will not transcribe it here 'cause it is long and probably not up to date. That said, you could always have a ticket for the reserved train with you to board (get past bouncer), and ask the conductor aboard or while boarding if they would be kind enough to accept your pass on that train. The unused reserved ticket can then be easily returned at a counter or Acela Club. Kudos to Amtrak for making refunds easy and possible.

These things I do not know for sure:

-I think these passes earn Guest Reward points but I have yet to complete a full 45 day period so don't know. Some agents have said yes points accrue, others have said no. This one is probably easy to answer with a call or two to Guest Rewards.

-I do not think any of these passes will work on Metroliner or Acela Express trains. I know for sure they technically do not work, but might an exception be made on a short trip (NYP-PHL) on an empty train? I have never tried.

I would love to hear any more insight from other pass users out there. Keep in mind that on some commutes the pass is not that great a deal due to small price difference, restrictions, possibility of loss of the pass.