If you search the book store for Steven Runge or Richard Stevenson, you'll come up with some titles that are published by "Logos Bible Software." I don't intend to create a thread of dissatisfaction over pricing, but I point it out because there is a price difference and maybe some might be interested in the Kindle versions simply to read.
Personally, I hope this allows Logos to reach a larger audience. These are great resources that I'm glad are not locked to the Logos platform, especially since they don't exist in print (to my knowledge). Meanwhile I will still gladly pay a premium for integration with the software.