I feel like you need to ask yourself, "Do I want to be in Prime Reading? And what do I want to get out of it if you are in it?"
Authors are reporting mixed results. Those that Amazon chooses--and when Amazon offers you a bonus payment to be in it-- they seem to be doing well. But if they choose you but don't offer payment? Not so much.
Amazon tapped book 1 in my most successful series last year. They did not offer any compensation or bonus for participating. I was in for 90 days. My rank rose in the store, but income did not. Not sure I saw any financial benefit or visibility benefit or additional audience build as a result of being in prime. (but now that I'm thinking about it, maybe I will survey my list and ask if any of them found me via Prime.)
And worse, as soon as the book was out of prime, the rank tanked, sales and borrows immediately slowed to a crawl. I have yet to recover my pre-Prime rank. A cruise through the FB groups and forums says I'm not the only one who has had this happen. So, just be aware.
