Quick followup to the comments made earlier in this thread. I got my new system (Win10 Pro i7-8700K) in yesterday along with the Syba SY-PEX30016 Firewire card and my Saffire (PRO 24 DSP) came online without issues using MixControl 3.4 (same version I was running over Win7) on Win10 Pro.
Ironically, I went hunting for Roland A-300 PRO drivers and got messages on Roland's site to simply connect it and turn it on, and that Win10 installs the drivers automatically. Even blowing that off and downloading the "drivers," they were nothing more than pdf notices saying the same thing

. Turns out it was accurate... just plugged it in, turned it on, and a few seconds later it came online. No configuration utility though, so will have to look into that later.* I was sorta spooked it wouldn't work from the comments I saw when Win10 first came out.
It is refreshing in a way loading a machine from scratch, since I am only going to install things that I use, not just because I have them. A lot of things are getting kicked to the curb on this machine.
*Quick Edit: I guess the A-PRO Control Map and A-PRO Editor are not OS specific, they are way down near the bottom of the Support page on Roland's website.