3DS to 3DS XL and then back to the 3DS?

I own both a 3ds regular (my main unit with all my downloads and stuff) and a 3ds xl (Nothing on it). I want to do a system transfer from the 3ds regular to the 3ds xl but I want to know if I change my mind about the xl if I can do another system transfer from the xl BACK to the regular. I also want to know if my special smash bros demo is transferable.