Currently the Logos price for this set is approx. $60 + change.
I checked out the two volume set on Amazon and it runs $4.99 in Kindle format. This is one of those seems too good to be true situations. My curiosity may win out, just to see if it is navigable as a stand alone ebook vs. being part of the Logos installation. Google sells it for $70.39 in ebook format which makes the Logos price look better.