There are slight differences in the padding of the early seats, some are firmer than others and not due to age or condition. I've owned 5 S2000's, my '00 had soft padding, my '03 was firm, my '02 is soft. I bought some '05 red/black seats, they were firm padding. I prefer the firm padding.

In terms of shape, there is almost no difference between AP1 and AP2, other than the headrest.

[attachment=97555:AP1 vs AP2 seats.jpg]

 

Having owned both I can tell no difference.

 

Getting in and out of my S2k reminds me of the process I use to get in and out of the cockpit of my sea kayak.