Thanks for all the help.... after trying all of the different mobi-to-mobi conversion options ([PDOC], [EBOK],
blank), and several hours of frustration

, I've come to the conclusion that just remembering my location when I close one reader and go to another is the simplest way...at least until someone with more patience than I have comes up with an answer. I don't care / need synching notes or highlights or bookmarks - but 'last' or 'furthest' page read would be huge.
Again, thanks for all the suggestions!