Like many people, I don't own a Pack Rat but I have been impressed by what I've read about it. Demos all sound great.
Josh did a hell of a lot of research and planning for this one and I hope he sells a ton of them.
Personally though, $250.00 for a Rat pedal is way more than I would ever spend, even if it does cover all of them. Most people will find one or two settings they like (and will actually use) and rarely deviate from that.
I built a Rat-based pedal using the LM308 chip and it has a switch for selecting 3 different pairs of clipping diodes. That covers the original Rat, Turbo Rat and the germanium, You Dirty Rat. More than enough options for me and it cost around $20.00.
If you get a Pack Rat, I'd love to hear your thoughts!