I've tried a lot of Bibles for the Paperwhite but this is the best KJV and easiest to locate verses. One can use the three tap method or just do a search for the first 3 letters of a book with a chapter and a "." with a verse (psa23.3).
This works perfectly on the Kindle Fire HDX as well. Thus, one can use this one Bible to read on one device, sync, and then continue on the other device. On the HDX text to speech works great with pauses at the end of each verse and the statement of the verse with the words to follow.
Now we need one like this with the NIV.
On the Paperwhite the Bible Encyclopedia available from Amazon can be made the primary dictionary and then each word can be looked up for more information. The Bible Encyclopedia does not work properly on the Kindle Fire HDX.
If reading any book on the Paperwhite 2nd Gen, one can search "all text" and get the Bible verse. Then return to one's place in the book. That cannot be done on the Kindle Fire HDX.
By the way, indexing on both devices took less than 60 minutes.
One can open the KJV in the Kindle for PC app, locate verses and then COPY and PASTE one's own notes into the eBook from other documents or apps. After syncing they will be on the Paperwhite and the Kindle Fire HDX.
Finally, the bookmark system on the Paperwhite 2nd Generation and the Kindle Fire HDX are similar with all bookmarks being addressable in the upper right hand corner. Thus, one could keep one bookmark for the Old Testament and another for the New Testament and read the entire Bible at one's own pace always able to return where one left off.