There has been a couple of comments posted Here about UA. It looks to have been greeted with mixed feelings by some of the members.
I found it quite different to the other Discworld books but that could just be me.
If you find a copy in a bookshop, have a quick read of a few paragraphs at various points through the book, you should get an idea from that.

I want to die peacefully in my sleep, just like grandpa. Not screaming and panicking like his passengers.
Don't drink and drive from The Lancre Tavern