I've been using Ubuntu Touch on and off since it announced
And, I just can't love it.
It's got naff gestures, a lack of buttons (it's a lot like Meego in that respect, if you liked meego, you'll love Ubuntu touch. If like me you hated meego, ubuntu touch is painful.)
I really, really want a proper Linux phone, and if I could get one with a better interface and less of the Unity, I'd be all over it..
I would point out though that anyone giving it a try now really should be aware of the limitations that it has as a work in progress. On a Nexus 7, for example - it's one of their reference devices, a lot of remarkably basic things don't work, like landscape orientation.
I want to love it, I keep going back, but the basic design just keeps putting me off. I hope they have an awesomely good product to bring to market, but at the moment, the implementation is leaving me cold.