I'm a little confused by what you mean with Unity (Gnome 3). Unity is not based directly on Gnome 3. Both Gnome Shell and Unity are based on GTK3 libraries, but they are still two different desktop environments.
That said, Gnome Shell has won me over (I voted Gnome thinking Gnome referred to 3.0+, as 2.X is pretty much over and done). I've gotten so used to it that using an interface that, well, isn't Gnome Shell drives me insane. It's solid, fast, and intuitive. It's running on my home theatre computer as well. It looks great while being simple and easy to use. Can't go wrong there!
Unity is looking good these days, however, Gnome Shell is just that good that I don't think Unity will ever sway me.