I'm a Kindle user, but not an Audible user. I bought a Kindle book recently, and want to gift the same book as an Audible gift. I've logged into Audible with my Amazon account, so it can see I own the Kindle book and is offering me the "Whispersync" price for the book. Can someone tell me if this is just a cheaper price for the same product, or if Whispersync is a specific product that won't work if the person I gift it to doesn't have the Kindle version?