Sky,

I use a Big Stick 40 for an engine break-in plane. I have had the following engines on mine: OS .46AX (2), Evo .46, GMS .47 (2), OS .50SX, Saito .56, Magnum .70FS and a few others I can't remember. All of these pulled it fine. The Mag .70 and the OS .46 were about the same. You can't go wrong with either engine. I did use a 3-blade prop some on the 4-stroke .70, 12-6 & 12-8.

With the .70 is was nose heavy. As a matter of fact, it was nose heavy no matter what I put in it. I put the rudder servo in the tail and used 2-56 rods for tail braces.

Excellent second airplane. Flies in any wind, lands easily, does all the acro except 3D. You'll love it. I do recommend you build the wing at least flat. Anhedral is better. Mine has the dihedral brace flipped over and it still rolls with rudder. (I was in a hurry.) It need 3 degrees on each side to stop roll with rudder like a low wing plane.

E-mail if you want more details.