I'm a big flightsim fan, for many years. Do have Flight simx and have considered P3D though not to hijack your thread but.. :-)
If you want realisim and like military stuff, you MUST check out Falcom BMS:http://www.benchmarksims.org/forum/content.php
It is an amazing revamp/improvement of Falcon 4.0, though it excels on so many levels it blew me away.
Just watch the vidoes and screenshots available - it is the simulation the Falcon 4.0 always wanted to be.
Just the flight simulation physics is so good, it feels right, whereas the original flew 'on rails'.
Just starting the jet up took me about 1 hour to get right, using all the actual controls - amazing stuff.
Also get FaceTrackNoIR for a el-cheapo version of trackir.