Try both: GMDX and Revision. GMDX is far better than Revision. It sticks more to the original Deus Ex.

I finished the game for the first time using GMDX a while ago. My old Windows PC is busted now, so I can't wait to replay it on the new difficulties.

GMDX is one of the best mods I've seen for a computer game, period.

I have a question. Why does GOG have Revision as a download but not GMDX?

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Yes, I guess your right there. Shame though as, even if they just mentioned it as an alternative to Revision, it might give folk some encouragement to try it. The Nameless Mod for Deus Ex is also getting an update, check out Mod DB folks.

I don't think so. It's a question of GOG not wanting to lose customers to Steam. The Steam release of Revision got a lot of publicity when it launched, and people were having trouble installing Revision on GOG versions. Having an "official" release on GOG helps mitigate that.

Yes, but how did Revision get on Steam in the first place?

I have a clear idea, from my own recollection of the happenings back in 2015, of how, why, and thanks to which unique situations Revision got to Steam. Going through all of it and maybe even checking online to give credible sources to my statements would end up with a sizeable text.

Regardless, I will not do that, because it simply bears no relation to the question you answered, and I have little incentive to do it.

If by "having the right connections and knowing the right people" you did not mean connections with people at GOG, then please elaborate. Since the person that asked the question has apparently very little knowledge on the backstory of the mods and even I, who have a meaningful amount of it, see no substance in your answer, imagine how little it tells them.

Your correct, I don't know anything of the backstory of these mods. I was only asking why GOG didn't include, either through links or a download, GMDX. The backstory, although interesting I am sure, isn't why I asked the question, rather could GOG do something about that, if possible.

Just bought Deus Ex during a sale. Should my first playthrough with with or without GMDX? I ask because I kinda want to experience the original, well, experience. Or is GMDX just so good that there is no point in playing an unmodded game?

Also, is there anyway to make it so GOG Galaxy launches the GMDX shortcut instead of the default launch shortcut? If I do play it modded, I kinda want Galaxy to track statistics. Or is that not possible due to the vast amount of differences GMDX includes?

I would play the vanilla game first.
Deus Ex is so good that it can be replayed, and you will probably appreciate GMDX even more if playing the vanilla game first.

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going to check out this mod on my next play though I used new vision and the hdtp pack.

"EDIT: Plot-wise, I'm not sure I agree with the addition of elite troops. It's like, uh, did they suddenly roll out nano augs to the masses or what? Magic?"

Thermoptic camo.