As someone who's not exactly Newbury St. chic or white collar but works in the Back Bay, I usually have a hard time finding a place in the area I can enjoy a nice lunch at without breaking the bank. It is indeed more of a hole-in-the-wall type establishment as like o mentioned, but it does fill a niche for people who are looking for non-sushi Japanese fare. If you want better ramen bowls, I'd recommend Ken's over at the 88 in Allston, but if you're in the area and are bored with the Boloco, Scoozi, and other ""cooler"" Newbury St. spots, try Mentei.
Pros: Different Fare, Fast, Not too expensive
Cons: Would be average if there were more convenient alternatives.