I'm in a similar position right now. I've got a '94 (with coilovers, racing seats, etc) and its really a fun car. But I'm considering selling it for an NB.
I'd really love to drive the car, and would love to commute with it a bit more. But the road noise is the real killer for me. With the soft top up, you hear every little vibration and every bump, I can stand it for about 15 to 20 minutes max. With the top down it's not bad, you get mostly wind noise which is ok ... except when you get on the highway, a semi right next to my ear is like instant-head ache for me. I could cruise around on back roads forever, but an hour on the beltway around DC and I'm ready to die.
I rode in a friend's 01 recently with the soft top up and it was completely different ... down right civilized. We could actually carry on a conversation without yelling, etc. I'm really tempted by the idea of selling my 94 and getting an NB.
My 2 cents ... if you're looking for strictly a track day / autox / fun car, get an NA. If you're planning doing any regular or DD duties with the car, get an NB.