Just finished the upgrade of my 861v6, HD621 and second system DSP5500 and all worked smoothly. The DSP5500s upstairs sounds less muddy and more delicate which was a nice suprise and the 861 seems more musical using Direct through my Adam Audio Tensor Betas and XLR out. Of course without a one to one its always difficult to tell whether it's wishful or real but I'm happy with the sound so far which is the main point :-) !

Also the recent Sooloos upgrades did allow my 24 bit files to work which had been a problem up till then where they would fail after a few seconds to a minute or so. That was also well appreciated as was getting pretty frustrated with that. Still not perfect though with the occasional stutter on to the next track when part way through so I'll see what difference my new router brings to the equation next week as my old Netgear does seem to be having the odd problem or two these days.

861v8, HD621, MC200, Sony S790, Panasonic 850, Adam Audio Tensor Beta's front, Adam Audio Tensor C9 Center, Adam Audio Pencil rear, Rel Studio 111 Sub and room mover.
Second system: MC200 direct to DSP5500 Mk1