I put in about 20 hours on FMS and my first day flying I did let my friend take off and then he turned the box over to me. I flew about 2 tanks of fuel and then did 3 take offs and landings by myself. Now this is just me and I've flown full scale airplanes, which I feel is very little help when flying RC, but I did it. Since then I've used a buddy box just for safety (didn't have the buddy box the first time out) and will continue to use it for a while. While I can fly by myself, that doesn't mean I should. I just don't want to risk my equipment and the safety of myself and others just for ego's sake. So the gist of all this is that, in my opinion, the simulator is a tremendous help. I just think it gives you a big advantage over someone who doesn't use one.
Hope this helps and good luck!
Danny Mullins