During the last 6 months I have had the (qualified) pleasure of comparing the raw bar offerings of these two bastions of seafood. No contest - The Lobster wins fins down.
At the Water Grill $75 bought the Deluxe Platter: 3 x 3 native oysters, 4 scallops, 4 clams, 10 black mussels, 12 Mexican shrimp, 1/2 crab and 1/2 lobster. At The Lobster $62 furnished 6 oysters, 4 huge Mexican shrimp, 6 green-lip mussels,1/2 crab and half of a 1 1/2 lb lobster.
OK, the $13 difference may seem to more than cover the addition of the scallops, clams, and 6 shrimp at the Grill (the mussels don't count since the huge green-lip more than match the little black fellas), but value for money doesn't compensate for lack of freshness and flavour.
Everything at The Lobster was top quality - the oysters briny, the shrimps meaty, and the crab and lobster chewy and very flavourful. In contrast, the seafood at The Water Grill was a HUGE disappointment, particularly the two crustaceans, which were, frankly, inedible. That they had been frozen and badly thawed was obvious - they oozed water and the flesh was mushy. After trying to salvage something from the crab, we gave up totally on the lobster.
To our discredit, we did not complain. My husband was so disgusted that a restaurant built on its seafood would serve something so obviously wrong, that we simply paid and walked out. I am amazed that it has managed to keep its reputation, despite now being part of a chain. The Lobster has nothing to fear from the SM newcomer.