[David N.]

In the '03 models and beyond they replaced the rear convertible plastic window with glass, which includes a defroster. With the plastic windows, there is no defroster. The defroster-button is in the '02 and before, but it only works on the mirrors (and the rear window if you have the Boxster hardtop currently attached).

Although the plastic won't fog as bad, I hear it can crack in cold temperatures. If you are dealing with frozen winters without a garage, I'd probably recommend either an '03+ or even better, buy a Boxster + a hardtop for winter use.

Good luck!

-David