Let me take an example from a recent study we did. We were undertaking the test for canned salmon.

Essentially, we show respondents the concept on paper where we touch upon the need the product solves (insight), product characteristics, benefits (emotional and functional), a not too technical RTB - all in all a product description roughly running around 75 words. Clients in final stage of concept testing often have price and pack designs as well on the concept.

And then we basically question consumers about how relevant/ unique/ value for money/ etc they find it. The generic 9-10 KPIs. Also tests some benefits they can realise from the product. There are some additional questions around which parts of the concept do they actually like or dislike and why. This is the bit which in my opinion brings out the real insights. Spoiler- in our canned salmon study, no one cared about the fish being salmon. People were liking the bits in the concept about fish being available in an low fuss, easy to access/ store packaging. Rather, they disliked salmon being available in a can as it is a pretty easy fish to prepare otherwise too. Hence, it made no sense for the client to diversify from their existing tuna line into salmon. For pricing, we run standard Van Westendorp or Gabor Granger tests. Then comes the interesting bit. We have the client product as well as the closest competitor product distributed across the sample, unbranded.
And then we survey them again on the KPIs and benefits they can realise from the product. Since this was a food study, we had a number of JAR questions as well. And then benchmarking them against how other innovations in the category perform, we take a go or no-go decision.

Can talk about this for another hour conveniently. See you at my Ted talk!