I've eaten there a couple of times recently, while dropping my wife off for a course with the Sailing school.
Menu - fairly ordinary pub menu.
Quality - variable! I've had two meals that were of at best average quality, but I don't think that's typical - I was unlucky. My wife's meals were perfectly fine.
Price - above average, taking into account the choice and quality.
However, after saying all that, there basically isn't a choice at present. The only walkable competition in Levington village (the Ship, I think) burned down earlier in the year! SO if you arrive by sea and want to eat ashore, the Lightship is the only game in town.