I have a DV9500 and had a Cary 303 cd player for about 2 years. Assuming the DVD6 is like the 303 then build quality (the physical weight and solidity of the player will be worlds apart). The buttons of the 303 have a more solid feel as well.
In terms of voicing, I find the DV9500 to have slightly hollow and shouty vocals. The 303 (assuming there is a house sound shared with the DVD6) had a smoother and more natural midrange but I found the bass a bit boomy and the treble was not as refined as I would like. Both the 9500 and 303 have some digital glare.
I share your concern re SACD software. Its sad that there are only 3,000 titles so many years after introduction. Most of these are classical, most (though not all) of the pop titles is from the back catalog (e.g. either I already have it on cd or am not interested in the music). That said, I just took delivery of an SACD player yesterday!