Just to reinforce the above opinions...

I did some research last year on this, before designing my "Eliminator 2" sport jet. ( http://www.nextcraft.com/j47_sportjet01.html )

I agree that 25% MAC, or a tad ahead, is the most often used position, and this proves that it works. Bob Violett, Yellow Aircraft, and a bunch of others do it that way, on planes that have proven qualities, so we know it works.

Hey, show us some photos of the rest of the plane !