Like USMC, I have used the Garmin 60CS for over 3 years, both on road & offroad, geocaching, and geodashing.
I did a direct comparison of the accuracy (as estimated by the units themselves) between the 60CS and the 60CSx - the CS found the digital satellites (yes, both had WAAS enabled) while the CSx did not. The accuracy reported by the CSx was worse.
I immediately contacted Garmin and had lengthy discussions about this, including the periodic struggles to find satellites, despite the new SiRF receiver chip. If you seach GPS forums (yes, there are more forums out there other than just thenewx.org and that unmentionable one) you will find posts discussing this issue. I have even seen this problem with the wife's GPS (Garmin Nuvi 560, which I will soon be selling to let her have a Tom-Tom again(better interface software)).
Bottom line is my Garmin 60CSx is supposedly working normally, so I still stand by my comments.