I find unity a highly productive DE. Workspaces work fine, I have the dock/unity bar/whatever only show up when I forget what workspace I put something on. It's not quite as customized as my Gnome2 set-up was, but it was easier to set up and works equally as well. Anecdotal evidence for the win and all, but I'm pretty happy with Unity from a productivity stand-point. I didn't much care for the versions pre-12.04, but by and large Unity stays out of my way, which is what I want from a DE.