This is a very nice, comfortable spot. The bed was very comfortable, there is plenty of hot water, and the bathroom was nice and clean. The unit is on the 6th floor and the elevator only goes to the 5th floor so if you are unable to climb stairs you may want to look elsewhere.
The location is great as far as sightseeing in Boston. The building itself appears safe with three codes to get into the unit.
I would give the place a glowing review. However, there are a number of homeless people nearby who regularly accost people on the street.