I have the Diabolic and really like it. I also like dealin with Zb at Esprit models. The one point I must make is that the weights he gives are a little underestimated. I have found this to be true in building two of his models (also the twin Diablotin).

You can see video of both of my planes on his website. The Diabolic flies really nice with a YS 91 and weighs just over 7lbs dry. It would fly well with a powerful 60. Its tough to put anything bigger on the nose cause its so long and therefore would require substantial lead added to the tail.

As far as flying though, the diabolic with the 80deg travel, full flying stab is quite unique. The waterfalls and elevators are tighter than anything out there, and it does some tip/knife edge spins that are mind boggling.

Good luck!

P.S. The diabolic is extremely durable. Thrice the plane has hit the ground (once shot down--failsafe went to full idle and full up elevator, twice the engine died in low hover). The total damage for these crashes was a broken motor mount and a small tear in the covering.

The instructions on the Diabolic are superb. I had mine ready to fly in under 8 hours.