There's a thread over on Rennlist where a 996 owner is trying to trade his car for a 993, some real asshat responses but several that do make some interesting points. One linked an ad for a 996 for sale that seemed to border on desperation imo, maybe it would be of interest to someone here considering the jump.
99 Porsche 996 911 Carrera C2 6 Speed $15k - Pelican Parts Technical BBS