Hi Linda,
I've been to Boston Lobster but not Cape May. In general, I found BL to be a decent family style joint. The price is a bit hefty if you aren't going to pig out, as is the case with most buffets, but if you're up for a non-gourmet seafood chow down (kind of the seafood version of the Old Country Buffets & like places if you are familiar with any of those), this is an OK stop.
BL has got a large selection of soups, salads, shellfish, fish, meat, etc. but it truly is all about quantity. For example, the crab legs and lobsters are rather small (which bothers some folks) but they are are plentiful and tasty. DH loved the mass quantities of shellfish (he learned to crack 'em in Maine and so doesn't mind having to deal with having to do it many times due to the smaller size which I know has bothered some).
I know a lot have been dissappointed by this place but if you aren't looking for anything fancy and your expectations are appropriately set, I think it's worth a stop.