As a foodie and chef, I would suggest going for really really expensive sushi establishment before coming to some lousier one to understand the taste.

Based on my experience of someone who deal with fish so much that I have my own set of stoopid expensive jepangis knives, usually, a whole salmon is very much enough for small establishment, and even to a big one, you likely need around 3 to 5 full salmon?

So, the taste ah, hardly varies largely.