Perfect location!
I stayed at this hotel recently while in town for the Boston Marathon. Despite the huge crowd for the marathon, the hotel staff was incredibly efficient, friendly, and helpful. The location of this hotel is absolutely perfect - right across the street from the Prudential center (and Prudential Center T station), very close to Symphony Hall, and 1 block from the marathon route. The hotel is also within walking distance to Fenway Park.
The room was average sized, but comfortable. There were really great views of the city from the window and the room was very very quiet - impressive considering the hotel was full. The room had a small refrigerator also. There are many restaurants nearby - both expensive and fast food. Near Symphony Hall, there is a CVS pharmacy and a Whole Foods Grocery store. There is a Starbucks in the lobby and a Cold Stone Creamery across the street!. We bought some groceries at Whole Foods and stocked our room refrigerator. Perfect for getting prepared for the marathon. My only complaint is the room rate was very high - but you definitely get what you pay for and it was worth it. 
The entire Back Bay area of Boston is a gem. We have visited several times and enjoy the area. Next time we come to Back Bay we will stay at this Hilton, if we can afford it!