Own the K10D, and DS. Have shot with Dl and D. Overall the Dl would be my last choice. Its only claim to fame is the 2.5" screen. The viewfinder is smaller than the other cameras. The Dl isn't made as well as DS. The real horse race comes down between the DS and D.
pros DS
faster shooting, faster clearing of buffer (D is really showing its age here - especially using raw.). Bigger lcd screen. Some menu settings easier. D has very small, resolution, white balance settings on top lcd. DS uses SD card like all other Pentax dslr. DS seems to need less work on jpegs than D.
pros D
Better built. More solid and more precision. The quietness! So much less mirror slap sound than any other Pentax dslr. twin control dials. Portrait grip. This allows twice the batteries for twice the shots and nice twin controls. Love the vertical release. More comfortable to hold with grip than DS. DS cuts into hand more. D without grip is closer to call. With grip D feels like small K10D/grip. Really nice.
Like both. Like K10D better than either.
Keeping DS as back up for K10D. Not sure what will happen if the K20D arrives.
thanks
barondla