Originally posted by Jim Woodward
....However, I did fly a UCD of another at the club field, and liked it (thinking ST2300 for it). Please, add comments. Thanks!!! 
Jim Woodward
ST2300??? IMO , Way to much angine for the UCD 3D. The power would be incredible but the weight would adversly effect the great flying characteristics of this plane. Also flight time would be effected as there is only room for a small (I think 14 oz) tank.
Most guys are using the Saito 100, YS91, or OS91FX. Although there are many combos that work great , these seem to be the popular choices so far.
As far as coupling goes, you are correct, there is a lot of rudder coupling but nothing that can't be mixed out with a computer radio. Also, moving the CG back helps a bit as well.
Again, just my opinion. Perhaps others have tried this combo with success.
...............Mark