Well, after five or six hours of testing last night, and unfortunately for the Zenith DVB318, there is simply no doubt that my Bravo D1 has a much clearer, more detailed and less artifact-ridden picture. I tried the Zenith at 720p (native screen resolution of may Samsung DLP) and at 1080i using the component outputs. It did look better than using the Zenith's DVI out (which I find really odd... DVI is supposed to bypass all the analog processing and therefore be a higher quality, more accurate signal).
But no matter... there is still the black smearing/ghosting problem (although it was less noticeable) and what I can only describe as very slight image "wandering"... it appeared to move around a bit (not a rock solid, stable playback). And, of course, there is the annoying fact that the Zenith stretches 4:3 DVD content (with kid's stuff, older movies, etc. this is a real pain in the a**). You have to reset the TV from "wide" to "normal" for the aspect ratio to be correct. And if the DVD is a widescreen letterbox (non-anamorphic) 4:3, the zoom function on the Zenith introduces some very weird scaling artifacts when you zoom vertically with the incremental adjustment to correct the aspect ratio. Also, it appears the Zenith overscans (crops) the borders of the image too much... you definitely can't see the entire frame.
I hooked my Bravo back up to the DVI and left the Zenith connected to the component ins to do an A/B... there is no comparison. At least with the Samsung DLP rear projection display, the picture quality of the Bravo is much more detailed, clear, stable, and has no scaling problems or other artifacts (unless they are on the DVD itself - i.e. compression grain, blocks, color banding, etc.)
I have to conclude that the Zenith DVB318 does have a pretty impressive picture over the analog component outputs. If you do not have a DVI input on your HDTV or it is a more forgiving display type than DLP (like direct view CRT, plasma, etc.), then the Zenith should be fine, as long as the 4:3 stretch thing doesn't bother you.
As for me, I will stick with my D1 for now. I haven't had any loading problems or other issues with mine and it is over a year old now. Maybe I'll have a look at the D2...
FWIW, IMHO, YMMV