Not a 4 star experience
Walking in to the large rather grand lobby of this hotel sets the standard high from the offset - but this soon began to fade as what was meant to be a quick check in took almost 20 minutes as the host couldn't find our reservation. After being made to feel like there was some issues on our behalf and complaining that they were 'extremely busy' (despite there being 2 employees on the front desk and no one in the que behind us) we finally were able to proceed with our booking. 
We were given 2 rooms on the 12th floor - overlooking the city. The rooms were large, clean enough but certainly not of a 4 star standard particularly the bathroom which was worn out and quite grotty. Our friends room next door had some issues though - and smelt so strongly of cannabis that it was a wander that cleaning services had allowed the room to be inhabited due to the stench. We informed the front desk about it and they sent a cleaner to use an air freshener which didn't really alleviate it but the inconvenience to move rooms late at night at this point was undesirable. 
Beds were comfortable and we found the concierge the next morning particularly helpful when trying to navigate around the city without much time. However some problems were encountered on check out when a member of our party realised after check out that she had left her gold bracelet in the room. She was not allowed to go back up and look for it, instead the hotel sent a manager up to search the room who came back with no bracelet or solution. Our group member was quite distressed as the item was of significant sentimental value and she would of felt better knowing she had looked herself but the hotel would not allow this - even escorting her to look around the room. Very bizarre service for a Sheraton hotel!
Wouldn't stay here again as it seems there is a good variety of 4/5 star properties in the Boston area that may provide a better experience than this.