Not a perfect crafting system, but much better than the default one. Crafting becomes a viable option for more complex items, and how the time is figured makes much more sense with this. Glad I purchased it!
My group and I were very excited about this book. Since it's release, our excitement has been scaled back quite a bit. Many things in the Downtime, Kingdom, and Mass Combat rules seem haphazard and not well thought out. It's got great ideas, and I'm not regretting my purchase, but be prepared to have many questions, and many house rules, if you want this to be a big part of your campaign.
Edit: Upon further playing, I have to rate it even lower. We've pretty much thrown the entire book out. It raises as many questions as, if not more than, it solves.