I highly recommend Realflight! Two things about this. First, spending a lot of sim time flying around in the sky wont get your model on the ground. Try to land from both directions and when you can do this successfully 10 times in a row half from each direction on the simulator, your ready to fly a model (with a instructor on buddy box backing you up). At this point, you may find it is actually easier to land the model than the sim because you have real depth perception, not a 2D screen.

Second, if you are spending a lot of sim time, and you find you are getting worse, STOP! you are regressing, take a break. You have reach the limit for a while, to continue to push on is a waste of time and will do more harm than good.