Never used it, but looks good.
Did a quick download and tested it, and it seemed to be a pretty fast product.
If you want a true testimonial of it, try the forum. There's a good list of people who love it, along with hate it.
Looked at the bug tracker and they seem to be on top of it pretty well.

Hope this helps :]

--m4rx

I've been playing around with it for the past week or so. It seems pretty good, but there don't seem to bee too many quality templates/skins out there for it. None that don't cost an arm and a leg anyway. Same with plugins/modules. I do like the ajax-based nature of the script though. Very "web 2.0".