I have the Beast3d umx with as3x. I would image that they fly about the same, the beast might be a bit more aggressive, but I believe all the electronics are the same (motor, battery, servos). Is it a plane to learn on...meh..more of an intermediate plane. It does stay nice and stable in wind, but it is still a quick little bird that reacts quickly. On the beast, you can put the control rods in different hole of the control horn to make it more or less aggrresive, I would assume the same is true of the pitts. I was up in the air over to pitts or the beast when I bought the beast, bought the beast because I wanted the 3d capabilities (even though my thumbs are not yet 3d capable)
So long story short, if you opt for the pitts, dial in some expo and dual rates, soften up the controls. The little bird will likely like to fly as fast as the beast.