It is nice compared to sitting in traffic. However if you are taking it from Providence, there is some bad news. It only goes 15mph from Mansfield to Gillette and it takes about 35 just for that leg of the trip. I spoke with a member of the T and he said it was the law. The tracks from Mansfield to gillette are freight tracks and therefore not safe for high-speed travel.
Last week I went with my brother & 2 of my nephews and we got to ride for free. If the train fills up, the conductors can't make their rounds and collect train fare. I got on in Attleboro and the train filled to SRO at Mansfield.