As the Duke himself would say, this game rocks!
This was the first FPS I ever played, and its remained well up on my list of favourites ever since. Even today, I would only put the various Half-Lifes, FEAR, & perhaps Far Cry as games that I have enjoyed more.
I always preferred this to Quake & Doom - technically they were of equivalent status, but the Duke's sly humour & frequent raunchiness always appealed to me more. And boy he was raunchy - I often wonder how the nudity, frequent S& M references and overall blatant chauvinism escaped the censors. Even today I still get a shock to come around a corner and see a beautiful & voluptuous babe chained naked to the wall - its something that's almost unique to Duke.
Technically the game has aged pretty well. The blocky graphics are only to be expected, and they dont really detract from the experience. AI is basic, but the enemies are ferocious & tough, and the game is still no walkover. In fact at the highest setting it can be insanely difficult. But its the humour that really sets it apart. Nothing is taken too seriously, in-jokes abound, and the multitude of carefully hidden secrets & Easter eggs to be found make the game very playable multiple times.
The real tragedy for the Duke, of course, is that unlike Quake & Doom there is no Duke Nukem 2, 3 or 4. The pitiful saga of Duke Nukem Forever has become a standing joke in the industry, but its really a tragedy of the highest order. I hope I live to see the Duke ride again one day - he deserves nothing less.