Hi Vuth,
The 9C super is the newer version of the 9C. I understand it has a few more mixes for gliders and such. I don't have one so I can tell you the exact differences. I do know that models can not be copied from the 9C to the 9C super using the Compac or any other device.
I have several different planes. The scale or size you want to fly depends on your budget and the place you have to fly. The smallest engine I use is a Saito 72. The three planes I fly the most have a Saito 1.80, Super Tigre 90 and a Saito 82. I will do a second post with a pic I took last week of my fleet. AS you will see I have a lot of different sizes and styles.
There is no difference between a stunt and aerobatic plane.

David