FMS is a freeware simulator, and can thus not be compared with the more expensive packages that is available. However, I can say that is is better than the previous RealFlight (not RealFlight G2).

Myself and my son (now 10 years old), both learned our skills using FMS, and according to my club's trainers, I went solo much faster than usual. All because of FMS.

FMS support is great, as they have a forum where all your questions can be answered, including relatively cheap interfaces, and even diagrams if you would like to build your own interface.

Have a look on my webpage, and go through the FMS links. Why not download the program, and try it out for yourself.