I disagree. I never knew about radds and used a sim for about 1 week. After that I could hover mighty fine with my DF4. 6 months later, using only a sim and the local clubs caliber 5 I can take off, hover, land, figure 8, and get myself out of most sticky messes (on a nitro). It really all just comes down to how well you catch on. My uncle came to my house and saw my DF4. He wanted to try it so I let him. In 5 mins he was getting the hang of it. He could compensate for nose in, side on, and looking at the back. 2 mins after that he was flying it 9not the best but he didn't crash). My point is it is down to how you learn. From using instructions. teaching yourself. Visual aid...etc.