RE: GP Super Decathlon
I have one, too. I have owned mine for almost four years. It is a great flyer but care must be taken. If you follow these rules you'll have a great relationship with your plane:
NEVER force it off the ground. Build up plenty of speed before you pull the stick back.
NEVER try to fly low and slow. It will snap without warning. I crashed mine on the third flight because I got too slow during my landing approach. It was rebuildable but barely. Since then I keep the speed up and haven't had a problem.
DON'T try to do a three-point landing. It will bounce-bounce-bounce all the way down the runway. Wheel land. This may sound contrary, but trust me. This plane does not like 3-point landings.
With the negatives out of the way, I can say some good things. This plane will do the neatest snap rolls you'll ever see. It will climb in knife edge given enough power, and flys well inverted. There is a little roll-coupling but it isn't too bad.
I think that you will find your plane is underpowered with a .46LA. You might want to consider upgrading to a .46AX or a .50SX. I powered mine with and Enya .50CX, which is a powerhouse, but I could still use a little more. Your plane should fly and be enjoyable with the LA, but it will limit you somewhat.
If you remember to follow the three rules you should have a long happy relationship with your Decathalon.