There is no need to go through the "logical" progression of 2, 3, then 4 channels. The PLANE, not the number of channels, determines how difficult a plane is to fly. Ailerons are no easier or harder to learn than rudder. You simply have to choose a plane that matches your flying skills. The only reason you would choose a 3-channel plane is because there are so many of them on the market. 3-channel planes are less expensive and easier to set up; it all boils down to the almighty dollar. If a company can sell more planes by making them less expensive, they will.

Frankly, I would be very hesitant about buying the Jobar, regardless of the fact that it doesn't look like a plane suitable for a beginner. It's being sold from Hong Kong, so the radio frequency may be illegal to use in the USA. The auction makes many very lofty claims, and in my experience, you need to take any and all claims with a grain of salt.

I recommend the E-Starter, set up as a 4-channel. It won't turn very well as a rudder-only plane, and you'll get into trouble. You need a more effective way to level the wings.