Hey Rondog,
I was actually intent on buying a '03 or '04 S, until I drove the '05. I liked it so much more that I opted for a base '05 over a '03 or '04 S. Of course my Base '05 has the sports package consisting of a 6 SP trans and PASM (Porsche Active Suspension Management) available as an option starting in '05, it changes the damper control map and lowers the car 10mm. This along with 19" carrera classic wheels make it handle unbelievably. There were a lot of changes in '05 that really made a difference to me. Including the new look, both exterior and interior. Also maintenance is now every 20K.
I know it doesn't have the power of an S, but with the increased HP and torque in 2005 along with the 6sp trans. I can keep up with a '04 S. Anyhow, that’s my opinion. I'm sure there are lots of folks out there that would prefer a '04 S over my '05 any day.
Here are a couple of links about the 2005 Boxster:
http://www.cars.com/go/video/motorweek/videoPopup.jsp?makeid=41&year=2005&modelid=391&loc ation=MW_L_2005_Porsche_Boxster_S.flv&aff=msnbc
http://www.seriouswheels.com/top-2005-Porsche-Boxster-S.htm
Hope this helps and good luck