To help you paint a picture as to what the actual seats are like; pretty much all of the field boxes are the same. There are four seats to a row with a rail extending down the side to separate field boxes. So it's really eight seats to a row but they use railing as a divider.

Easy to get out of the row but your knees will be in an uncomfortable spot. I would recommend anyone over 6'3 to sit on the Green Monster, State street pavilion, or standing room only because the seats are extremely uncomfortable for some people. But in terms of proximity to the field, it doesn't get much better than section 57. You're basically front row center when runners are heading for home.