Well, converting from my 1st gen ES to the SSEi was a night and day conversion. The seats are 10x more comfortable, they are heated, the stereo is 10x better than the stocker in my old 'trep, the heads up display is great, and the orange/red lighting really does reduce glare at night.
That said, there are really only a few things that I don't like about the interior of the bonnie. The climate control seems to have to have a setting much hotter than the intrepid to make me feel comfortable (77*F instead of 70* in the intrepid), there are no cruise buttons on the wheel, there is no cruise light indicator (not much of a problem), and you can't have 2 cups in the front seat cup holders at once. But all of those are VERY minor problems for a great handling and very powerful car.
1994 Intrepid ES - 3.5L w/ 167k miles - SOLD 04/01/04 for $2200 - Man do I miss it!