Let me be frank right up front: my dining experience was mixed by my own fault: I was dressed in jeans and a t-shirt and that proved to be totally inapropriate for 'Pod Lososiem' (which means 'Under the Salmon' by the way). The food was fantastic! I only ordered main dish which was trout in mustard sauce, but they brought me a little apetizer on the house (really little, it was a little fried tomato, wrapped with some bacon with sauce; very nicely presented, nice touch). Everything looked meticulously prepared and presented. The beer I ordered came in a gigantic stein featuring the seal of the City of Gdansk, the capuccino came with a little piece of chocolate to stir it with.
The decor of this place is awesome! Dark wood, dark interiors, expensive chandeliers, well-attired wait staff all adds to a very pleasant dining atmosphere. Which brings me to the definite low-point of my dining experience... Being totally under-dressed for the restaurant, I got a very cold shoulder from the door man, and I noticed being observed a whole time I was in the restaurant. The barman was sitting by the bar, wiping the same beer glass for about an hour. My feeling is: maybe they though I accidentally wondered into the wrong restaurant, and couldn't afford anything on the menu.
So in a nutshell my recommendation is: go and try the wonderful food and decor, but dress nicely. And try the Goldwasser if you feel like splurging a little. It's a traditional Gdansk liquor with flakes of real gold in the bottle.