Yes, with a Sony GDM-FW900 (24" 16:10 widescreen CRT) and it's awesome; HD in its full 1080 glory. I've never tried it with a 4:3 monitor though. It should sync, but I guess it depends on whether the monitor will squeeze the picture down enough so that it is the right aspect ratio.
One other thing: the gamma curve for a monitor is different than a TV. Greys go to black faster, so I would say that the picture is just a little darker overall, and if the scene is primarily shadow, it's pretty dark. This is mostly a problem with shows filmed like The X-Files, i.e. mostly dramas. Sports, sitcoms, shows set in Hawaii: no problem.
This is very monitor dependent as it would sync differently to the signals. I have an old SUN, sgi and Sony that all sync perfectly to 1035i, 1080i and 720p via RGBHV.