My main sim is FS2004 @ roughly a 45 GB install. I mostly fly my Alphasim Raptor F-22 with a customized cockpit. See this video.
https://www.youtube.com/watch?v=9SQpIEyR81I
I am flying into my created Area-51 taht I have worked on for years and have all sorts of military both classified and not like Janet fly in and out of there. The Janet airlines have real world flight scheduales and fly to the real life destinations. I use the 737-200 and 737-600 models. They don't fly the 737-200 anymore. Did you know the government bought the 737-600's from China? Not even the government can help but buy from China it seems.
I also love my PMDG 737 and flew it on VATSIM. I been to all sorts of locations with that plane. From Hawaii to Christmas island to Fiji and New Zealand. I know how to use the FMC and the works. Can read and use SID and STARS which is required in VATSIM.
I do have FSX Deluxe, but haven't played it that much. I want to get the PMDG 737 for FSX because it has more features than the PMDG 737 for FS2004. Like a HUD and selectable break types. You can freaking chose what type of breaks the aircraft has!
I also like flying my Beechcraft B1900 D/C. See this video.
https://www.youtube.com/watch?v=PQvYoUoBwWg
If you want to earn real flight credit fly prepar3d. A lot of aircraft and addons fof FSX are compatible with prepar3d.
http://www.prepar3d.com/ It's pretty much the same thing as FSX.
Flight Simulator is a huge CPU hog and you can have the fastest CPU and still not be able to jack the settings to max. In FS2004 I had to turn down autogen when I flew into DC. It was giving me like 2 FPS with all the buildings. Even in New York. Nut most other places I can set it to high.
Get this. I bought CH Products yoke and pedals from a yard sale for $20! They can both run you over $200 on ebay. LOL!
This is the book to get if you want to fly the 737 like in real life.
http://www.amazon.com/737NG-Trainin...=UTF8&qid=1400195581&sr=1-1&keywords=mike+ray