AS Jontahon pointed out, market research does not tell you whether your customers will actually use the product - it simply tells you whether they like the idea of it.
This is called Attitudinal liking - your attitude towards some product is positive, but when it comes to opening up your wallet you might decide otherwise. For example, lot's of people admire Macs, but purchase PC's.
Therefore, there is no other way to test the product other than actually launch it and see how it goes. The wisdom is to find a way to invest as little time and money to launch a functional product you can test, then build on the feedback you get.
Before that, make sure you understand the market you are entering, which means you can answer YES to following questions:
1) Does your product solve a specific customer problem or issue? (product benefit)
2) Are there enough customers who have this issue? (market size)
3) Are customers unhappy with current solutions or solutions do not exist at all? (competition)
Hope this helps.