Seriously?
First of all, the "Regularly $31.99" app was set at that price a bit more than a year ago… for one day. (App Shopper says it was $38.99, in fact.) Since then, the price has ranged from $1 to $10 on the app store.
As far as I can tell, the only reason to even download this app for free is if you do a lot of splitting and merging of pages between PDF files and dont like the was Preview does it. But unless this app is hiding features somewhere, it seems to be nothing more than a minor subset of the features found in Preview, an app freely included on every Mac.
Why anyone would want to pay for this is beyond me. It may do what it says it does, but you already have an app that does it--unless, like I said, you cant deal with Previews interface.
BlogD about PDF Magic