Well, I tried it without Unity, but Gnome 3 was a mess for me. I felt a huge loss in productivity. Some things were missing. For example, I use emblems (in Nautilus) to organize some documents, flagging them (mostly banking documents, flagging them as "paid", "late", and so on). Also missed Compiz, not for the bells and whistles, but for desktop switching (mouse scrolling on the desktop background), and for instant screenshots of an area. I used ctrl-shift and marked the area I wanted, and a script I wrote would scp it to a public server and show the url with zenity. It's nice to be able to send instant shots to people on IMs like this.
I still couldn't make Compiz work nicely with MATE on Mint, but I did manage a workaround for the screenshot thingie (using 'scrot'), but I lost the desktop switching (must scroll in virtual desktop applet in the panel), but it's more acceptable than Gnome 3 (at least for me).
I can say I went to the new Ubuntu with an open mind to really try to like Unity or Gnome 3, but after 2 days running, I was so pissed off I almost installed Windows. I am ok with changes, provided the changes make me work better with my computer.