Highest quality: Fearless Fish. The cuts he sources are just gorgeous. This is 100% the place to go for sushi-grade, no contest.

Best value: Tony's Seafood (but their selection is super limited because they just closed for renovation. They do offer delivery though, which is a plus!)

The one that got me into seafood: Local Catch (super tasty and good quality just more expensive than Tony's. They're also super friendly and offer home delivery as well.)

These are the main three where the quality is consistent + are the most convenient. There are plenty of others that are solid. There are also plenty to avoid so I'd stick to the ones everyone has recommended in this thread.