We have the RF sim and I think it could be a real help. One guy who joined our club last year practiced on it before he ever flew RC. I don't know how long he worked the simulator, but after two sessions with an instructor and buddy box at the field, he was on his own and has been eve since.
All in all, there are a lot of variables to consider when making that transition.
I do have a Top Flite DC-3, and also set up the one on RF just like it, and they flly surprisingly similar. I did a lot of simulator practice before I flew the model, and I think it helped, at least as far as landing approaches, and getting the feel of the flaps.

Good Luck,
Randy