KOTOR is a great game. The graphics are not as good as Deus Ex, but after playing it for a short time you forget about that.
The story grabs a hold of you and does not let go until you finish the game.
The turn based fighting system put me off a bit at first, as I've never played a video game that had that, but once I found the pause between attacks/turns feature I was able to control attacks more stratigically and enjoyed the game even more.
Deus Ex's graphics look good but the story line just did not strike me as very intriguing.
I found myself going through the motions,plodding along to see what was around the next corner, not really caring what the implications of that might be.
I couldn't get emotionally attached to either of the two groups that they offer for you to ally with.
Maybe I did not give it enough of a chance, (I played it until I got the secret weapon that MAKO was developing)
KOTOR, in my opinion, is the better of the two games overall, though Deus Ex, as a diversion, is okay.