We stayed at the Commonwealth for 3 nights in March for a wedding. Upon check-in, a very friendly employee offered us a champagne toast, and unexpectedly upgraded us to a Junior Suite. We overlooked Kenmore Square, and even though we were only the second floor, heard no street noise. The room itself was very large and very comfortable. I also tried out the fitness center which was small but very nice. Each machine has it's own tv and they provide earphones which was extremely thoughtful.
I had taken the T (subway) to the hotel, and it's extremely close, actually on top of the subway. There is also 2 amazing restaurants and bars in the hotel. Both are delicious, reasonably priced, and were great atmospheres.
The hotel is also walking distance to Newbury Street, a great street for shopping and lingering around. Highly recommend this hotel for a great location and great service.