Hi David,
the best way to determine would be to compare the MK kit with the Hobby Barn kit (and yes, I have both). I have to believe that something happened when the mold for the glass Magic was created. Certainly, I can't believe the original had issues since Hanno won with it. I have never seen an MK Magic fly, and only one Hobby Barn Magic which flew well, as I recall. It belonged to Willie Macek (he built a pair of them) and was powered by a YS 60FR - they were heavy, I think Willie told me about 10lbs, but he had a lot of success flying them.
It is a very cool looking design and with the mixing capabilities of current radios I'm sure even the 'Tragic' could be made to fly quite nicely.
-Will

by the way, MK also kitted a glass fuselage version of the Magic - I have a photo from an old MK catalog. Since MK is now out of business, maybe Chip can contact them about purchasing their mold (if it still exists).