No, I think outsourcing this is at worst dangerous and at best lazy. Furthermore, unless this is highly focused on a type of user, I wouldn't trust that you could build user panels that were really of my potential customers. And therein lies the rub. Without real customers, it's impact and value is low.
Interesting way of stating the question. People pay business consultants all the time for that same information. I get paid to probe the idea or concept and provide sound guidance to the founder. So, if what you mean by service includes the hiring of experts, then the answer is yes.
However, if you are referring to a SaaS type model, I would approach it cautiously as a potential user. It would seem like a gimmick on the surface - much like all those personality tests that are not scientifically based. If the idea is to have me answer questions, then tell me the odds of my success or failure, I would be skeptical. So, unless you had some tremendous authority behind the service, I would personally not pay for it.
That is not to say it will not work.
What I would pay for is a SaaS program that asked me branching questions to help me flesh out the concept. In other words, I am asked a question about my business concept. Then, based on the answer, other questions are asked that cause me to think of things I had not already thought of.
The concept is similar to the book I am close to finishing where I am asking hundreds of questions of would be entrepreneurs to get them thinking.
I might even use a service like this with my own clients as a value-add.
Let's get on a call to discuss this further. The first call is free with this link. Go ahead and schedule some time choices to get started.