I would think the breakfast at the Westin restaurant is going to be more worth your while. I stayed at the Marriott twice over the past few months, and I wasn’t at the hotel in the evenings so I can’t comment on the evening offerings, but breakfast was just okay. A step above the typical Marriott or Sheraton lounge breakfast in the US (for example, they had one type of cold cut and one sliced cheese; a few more pastry options), but overall still pretty mediocre.

There is a bartender in the lounge in the evenings, but I’m willing to bet the price of booze is going to much higher compared to just going to a regular bar in back bay or the south end. (And if you’re looking for a drink close to the hotel, I highly recommend The Salty Pig, which is adjacent to Back Bay Station.)