Although I have #Solus 4.4 #Budgie installed on a #Razer 15 laptop, which updated from 4.3, I went ahead and installed Solus 4.4 #Mate on a Dell #Optiplex 755 Desktop.
Smooth as a hot knife through butter!
No issues at all.
Least I can say tonight that I actually did install 4.4 from ISO.
Chose Mate on this spare machine, so I can follow the eventual process to #Xfce out of pure interest.