I don't know if I'm looking for an excuse to upgrade or and excuse not to. I installed win 10 on my laptop a while back and hated it. I installed it on my work machine and it's growing on me. It's totally different though. I think the laptop may have been installed for a tablet, not sure.
 
Anyway, are there any performance improvements in SPLAT to make it worth while to upgrade to Win 10?

I would recommend looking at this post (ESPECIALLY Noel's post)
http://forum.cakewalk.com/Sonar-meltdown-Failed-upgrade-Now-Sonar-wont-run-at-all-m3396892.aspx
 
Note that your Firebox does NOT have a Windows 10 driver and Presonus does not intend to write one...
 
I had an old Presonus FirePod.  I actually tried to get it to work on Windows 10 and could not no matter what I did. 
 
I have Upgraded to Windows 10 and switched interfaces.  I now use a Behringer XR18.  I know Behringer...But it does have very nice Preamps.  TERRIBLE documentation, but the forum helps.  If you need anything higher than 48/24 look elsewhere though.  I do not so it works for me.

Thanks for the info on the presonus. I was going to put it on my work machine, but I guess I can't now. I'm using the Focusrite 18i20 in my studio though.