I have never flown a cub, BUT I can not see why you cannot learn to fly fixed wing with it - if you have an instructor like the others suggested. Even if you had a trainer you would be recommended an instructor. Go for it - the price seems good. But yes don't go flying fixed wing with the idea in your head it's the same as helis. Flying helis you will have a good idea of orientation and the controls - but I have flown helis before I flew a plane and it's not the same. However since I was familiar with the sticks and the orientation and put time onto a simulator I could solo my first flight on my US (stupid buddy cable didn't want to work lol).

Good luck and remember the most important thing - have fun.