The game has aged quite poorly, but I managed to play it to China. Then the difficulty killed me so I had to turn on the magical hack powers of hacks and finish it. The story is still fantastic though. As much as I'd hate to say it, Deus Ex: Invisible War has held up a bit better in terms of gameplay, but the story is still terrible.
Really, people struggle with Deus Ex? Well, I suppose you have to be good at the stealth aspect to beat it on the highest difficulty. I always went for the stealth kills and plenty of explosives so I never had much trouble.
Deus Ex really hasn't aged well though so I actually don't feel that compelled to play it again since Deus Ex 3 turned out to be a near perfect sequel.