Since you plan on a 450 size, the best way to train on the sim is to use the Axe CP, turn the gyro gain down a bit, and turn the physics speed up to 110%. Use a smaller less stable heli, and crank the speed, and when you get that one down, as long as you take your time on set-up, and preferably have someone experienced help you, and follow Radd's, you should have little to no problem going to a real 450 heli.