You won't ever find a more thorough constucted and well made kite than one of Heikos kites ...
They are expensive, but well worth it.
I dabble also in designing kites (LevelOne Eternity) but I would never, ever consider myself just near the league Heiko is in.
That said, for that price you better first find a way to test-fly one of the X's.
It may be the best kite in the world, but if it doesn't work for you and your style ... then it isn't the best kite for you ...
"I started out with nothing and I still got most of it left ..."