just a update for anyone that may read this,
 i put a gms.47 in mine i didnt like it. it was to nose heavy even w/ the engine as far back as possible and the plane would not harrier/float what so ever, it just wanted to stall when i slowed it down even w/ flaperon at 15 degrees.
w/ the fp i need 1 oz up front and the engine as far forward as possible to balance. it flies very well both w/ and w/o flaperons, you can slow it waayyyyy down which is really cool.
i think the os 46 la would be perfect, the 40fp (similer to 40 la) can almost hover on a apc 11x5 (going to try 12.25x3.75), and i bet you wouldnt need the oz up front to balance