Although its my first post, I'll put my $.02
I just went through this same thought process. I was originally looking for the same cars as you. An early S was my pre-drive favorite.
When I finally got around to driving a couple of cars, the 987 base was way more composed and comfortable for a daily driver. I like performance as much as anyone, but the difference made me feel much more confident in pushing the better composed car, vs. the more raw early S. Plus as you have stated, and many others, its still under warranty and its newer etc. etc.
The 10 hp difference, I couldn't feel, as the car is quick enough for me (for now). To top it off, the dealer found me an '05 base, super low miles (break in miles) w/ the options that I wanted, and a few I didn't(!) at a great price (mid 30's).
I jumped at it, and haven't looked back. These past three weeks the only problem I've had is that my face hurts from smiling so damn much
Jason