Uncertain. As a shooter, I found it to be somewhat underwhelming even upon release - but I was never much of a singleplayer shooter fan.
Game has a lot of large empty areas - and it was never as tight as Quake or Doom. It was more of a technical marvel.
I think the engine holds up very well considering its age - and if you're interested in the history of gaming and such, it's not a bad way to spend your time, I guess.
From memory, it's also quite a large game.
This reminds me of Unreal 2, by the way.
Unreal 2 was relatively poorly received, but I loved it. One of the better shooters, I found. Mostly because of some pretty amazing levels and atmosphere - though I'm not sure they look very good today. It was much shorter than the first game, but it had some interesting alien weapons - and some neat lighting effects.
Could be worth a shot, too.