Albeit that I had started off with my first departure being cancelled due to a snow storm- I found that my bus drivers were good.
Mr. Monroe gets a 5 (drove back from white river junction to mtl)- the bus lacking wifi gets my "meh" 3...
Going to Boston is a long ride- most definitely suggest the overnight bus. As far as new drivers? Could potentially make your bus an hour late on arrival- "but, you didn't hear that from me" xD...
Also- when purchasing your ticket, remember! Deciding to postpone can mean all of an extra 40-50$ (around 3 weeks to departure date) just don't be tardy.