I have both FS 2002 and FS 2004 installed on my computer.
I have tried both but I actually prefer my up-dated version of FS 2002, and that's the one I use...

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(To get reasonable frame-rates on FS 2004 I find I have to wind the cloud effects down, so then it's no better than FS 2002, and ATC chatter on FS 2002 is O.K for me...)...

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My overall opinion is that if you're happy with your FS 2002 and the way it runs, and have difficulty in finding the pennies to buy FS 2004, then stick with FS 2002 for a while...it's good...

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Cheers all...

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Paul.
(England).
Win 8.1 64-bit. DX11. Advent Tower. Intel i7-3770 3.9 GHz 8-core. 8 GB System RAM. AMD Radeon HD 7700 1GB RAM. DVD ROM. 2 Terra Byte SATA Hard Drive. Philips 17" LCD Monitor. Saitek Cyborg X Fly-5 Joystick. ...and a Briggs and Stratton Petrol Lawn Mower.