Which flight simulator is the best ?

I personally feel:
Real Flight G4.5,5,6 are good ones since these have a wide variety of models. Apart from real flight you could select Phoenix RC as well. Both these come in the simulator set that are available on different stores.
Try www.rcbazaar.com
www.rcdhamaka.com
www.quadkopters.com
www.edallhobby.com
www.rcbharat.com
There are chances of out of stock, so you need to search for it.

What about AFPD?

I like RealFlight but I keep going back to AFPD every now and then.

aerofly RC 7 !!!

I been using this since long time and the graphics are just amazing !!! really amazing !!! ... supports any controllers !!!

Thanks for the sticky

aerofly is the most expensive!