I waited until I resolved some issues with main system, so installed Daz6 yesterday. As mentioned, it installs as a separate program so nothing is changed to ver.4.

Initially, it seems snappier in most aspects. 
Wish there was and (maybe there is/will be), a way to import menu items, Workspaces, and such from 4.x.

Still kickin' the tires, but my "biggest" new favorite thing so far is this little item: