Hello Matty....

...
I have both FS 2004 and FSX on my hard drive, and with my Computer spec shown below, my FS 2004 runs smoothly (most of the time) with everything maxed, and FSX runs fairly well with some of the settings wound down somewhat.
So in the end it comes down to which Sim gives me the most
satisfaction on my existing hardware, and I must say, it is FS 2004.
With that in mind, and to save the big expense of a brand new Tower computer, I continue to enjoy my FS 2004 daily, and just occasionally run my FSX, for a slight change.
Its the old choice...Want versus Need!...

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...!
Paul.... 8-)...!
P.S. Its always good to see Folks still enjoying their FS 2002, and still using it for FS Host Multiplayer Sessions!
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.