Hi,
The pass is good value if you want to take long distance rides, but as others have mentioned, it is not such great value on short hops. You can use it for longer trips and pay seperatly for the short segments, as suggested above.
The main drawbacks of the pass are as follows: It is only valid for a limited number of rides, taken within the validity of the 15, 30, or 45 day time frame. Each time you get off a train or amtrak bus, you use up a ride, same if you break your journey to sightsee, and get on the same train next day, that break is counted as a ride from your total available.
A very annoying complication is that once you buy your pass, you will then need to make your actual train reservations for your routes..
BUTat that point, Amtrak can ask you for more money! If the train you want is busy, even though coach seats are available, your pass is not usable as it is.. you have to pay a supplement!
Kind of cart before the horse.. you buy your pass, but don't know if you have to pay extra untill you choose your trains!
The roomettes are a seperate issue, you will have to pay for those anyway, and as mentioned, you pay the same roomette price as the going rate. Roomettes are cheaper to reserve far in advance, so once you make your pass reservations, make your roomette reservations in advance too, for best prices.
Another point with roomettes is that if you reserve a sleeper berth, your rail pass will be valid as is for that trip, you dont pay any coach supplements in sleeper. You can decide to ask for a roomette as late as on the train itself.. sometimes they are available then at the lowest prices, but it is a big gamble.
To be fair, it might be that 99% of the time your pass would be usable without supplement, or it could be 60% or 5%, no one knows.. best advice is plan your route, see if all sections are priced at low bucket prices, and decide from there.. if all sections are lowest bucket price, your pass would be valid. (Bucket is just a jargon term for price increments, or steps.)
Your month long trip sounds a wonderful project, however you go!
Eddie