As much as I own Cubase 7.5 (Cubase 7 is dead and gone on my part), I still use Cubase 6.5.5 for client work.
I have installed C7.5 on three different test machines (both win7 and win8), more or less to keep score of the developement. I’m not liking the new Control Room thing and the mixer looks and feel a bit “toyish”.
Many great ideas in C7.5. And I like the Track Versions (can work like in PT and S1), the Track Visibility list thing, and Tab to Transient (even though it does not use the Tab key???).
But all in all, coming from mostly using other DAW’s for the last year, Cubase 6.5.5 is the best Cubase version so far. For me 