My favorite thing to do in gymnastics is a layout full on the floor because it invovlves both twisting and flipping - and because it took me awhile to progress from the half twist to the full twist.  But now I can double twists on tumble track, both forward and backward.  So I feel like learning the full twist was hard, but I mastered twisting after that.  Now it's all a question of building up enough power to attain the height necessary to do double fulls on the floor.