We love love love our Snow crab/ King Crab. So we ventured to both the Curb Market known for its fresh crabs and the Nijo fish market.
Between the two, I prefer the Curb market.
The crabs are fresh and alive, you pick the ones you want, and they cook it for you at their restaurant which is just behind. It's more spacious for dining compared to Nijo.
We liked the Curb market so much, we went back twice more, and one of those times we brought Jo Anne and Jimmy who were holidaying in Hokkaido too.
The fresh crab is steamed for you (or you can choose to grill it yourself on the tabletop grill). So sweet and plump.
They are friendly, not pushy. No sneaky hidden cost or what. Agree on the price when you choose your crab, and in you go... to enjoy your feast. Be prepared to spend several hundred dollars though, King crab is not cheap, anywhere in the world. But here it's so fresh and good.