You can usually find them on sale on RC Groups "for sale" forums pretty cheap.... used most of the time, but in "like new" condition for around $60-$130 depending on version. I got the Deluxe version of Aerofly Professional with the USB controller for $125 but that was a steal.

I would recommend either version that you can get at a good deal. I flew the non-deluxe version for 1 1/2 years before upgrading to Deluxe. There's some difference in the new one... graphics, new[better] planes, new[better] sceneries, flight physics, etc.

Gary