Hi Ian,
I'm sure many do get caught up taking that step of actually entering the market. My advice would be, most certainly use the research tool as a guide, but don't let it govern your decision making completely. Sales of products can dip and spike for a lot of reasons, especially if you are looking at the results of short term data only.
At some point you need to put theory into practice to really test the market, and that's where basic marketing research actually turns into test market research. Test market research is taking all your prior research and testing that by putting the product online.
Test marketing is the only true way to get the correct data because it's sales based data direct from your own business model, no one elses. Meaning that if the product works, it's working at a price you can make money on, it's working from a supplier you are buying from and it's working in the market you have chosen.
These factors give you hardcore data that you can then streamline if required and build on if all is good.
I would suggest trying a few different avenues, something like listing one at BIN, then the other at auction with a starting price to cover your cost. Even starting one at 0.99 to see how that works (unless the cost of loosing money is too great for you)
This is what test marketing is all about, using the research you have and then finding out how best to sell the product or if in fact your initial research was accurate.
Once again, product test marketing can take a while to get accurate data because of short term market forces causing dips and spikes. I would suggest many list a product they thought they had identified accurately as one with potential, however after listing for a week and getting a bad result, they walk away from it.
You do have to use your head, no good throwing good money away on a bad product choice, but it's no good throwing a good product choice away on bad short term data either.