I have a Pizazz with the OS 70 II and APC 13x6. It does seem to hover a little better with the 13x4W and I've even run the 14x4W but it spools up a little slow. Mount your elevator servos in the rear just before the stab. I cut holes in the fuse side, added some servo rails, and went with pull-pull to each elevator using HS-225MG's. Then the rudder servo was mounted in the bottom of the fuse. I didn't need any tail weight using this method, and I have ailevator set up to help the torque rolls. I like the way it flies but I've flown better hovering planes. I would like to sell the Pizazz I have with the OS 70 and get something like a Razzle for a Saito .91 I have. I think the Saito .91 would even be good in the Pizazz but at 5.5lbs it's getting up there already. I have heard of a Pizazz with a 91 two stroke ducted fan engine in the nose. Talk about hover power!
-Tom