To give you a reasonable answer, it would be very helpful to know what kind of super cub you learned on. If it is a glow model, then it is probably a step above the nexstar when it comes to flying skills required. If its a park flier model, then the nexstar will probably be a suitable step up. You will need to be aware of any control differences between the two planes, such as having aileron control. So in summary, let us know what kind of super cub you are flying and then it will be possible to gauge what your skills are probably like at this point.

P.S.: Please turn off the caps lock. Its a bit difficult to read a message in all capital letters.