Specialized SL Range Extender Battery.... is it worth the investment? (in depth testing and review)

Do you have a Kenevo or Levo SL?? are you contemplating the range extender battery? if so watch my detailed real world test of the battery for MTB purposes to find out everything you need to know from real world range, to how it fails over from external to internal battery. Find out how far you can really go as it isn't an extra 40 miles! does the price warrant the range?