I do not understand the allure of Kindle Unlimited. As I understand the service, for $120 per year you can borrow (not buy) all the books you desire from a large but limited library. When I say limited I mean that you will not find any books there that are written by known author’s. The authors you get to choose from are the same ones you will find giving their books away for free on sites like DaileyFreeBooks. Each day if you subscribe to that newsletter you will see over 2000 books absolutely free with no gimmicks.
Now if you really want to borrow books why not do it from your state library’s digital service. You pay nothing for that privilege and you find books from Patterson, Koontz or most other familiar authors. The only draw back is that you sometimes (often times) have to stand in line to get the book you want. But between that and the free books available I would guess you would always have more books in your Kindle than you could ever read.
But if you are still not convinced check out my author’s page.