Thanks a lot for your respones, keep sending them if you read the poll !
What I learn from the responses till now is:
Could be a market for it, I've had a high reply rate for the number of views until now, compared to other topics on the forum. So the interest is out there.
If possible should be a two seat. I agree, although building cost go up more quickly for a two seat than a smaller single seat aircraft. As a first guess the $200,000-$250,000 mentioned would not be far off, lets say it compares to a Lancair Legacy. A single seat could be build for probably less than one third that number, which is much more affordable for a lot of people.
There are a number of small (micro)turbines available on the market (look at the SubSonex) with reasonable good specific fuel consumption numbers. Although getting a 1000 Nm range would not be realistic. 500 Nm would be a more doable number, which is not to bad?
After all it's having the fun of flying the airplane and doing aerobatics with it. With modern composites you can have thrust to weight ratios of about 1 to 3 or 1 to 4. So the prformance will certainly be there.
Again thanks a lot for the replies, looking forward to receiving more opinions, also from other people.