I leased a 2014 i3 REX with a considerable amount of consternation but have found my fears to be generally unfounded. Have had the vehicle for approx a month, I've only had to use the REX once in over 1200 miles. My usual driving falls well within the electric-only range of the vehicle and so far I've only charged off the Level 1 charger (120V) at home though I do plan on adding a Level 2 charger to my home. Consider your daily driving habits and take a look at what your longer driving days may require as well - keep in mind that the level 1 charger will fill that battery at ~ 1 KWh per hour so AT BEST you'll get 5 miles per hour added to your battery (ECO PRO+ mode driving). City driving yields better range - highway driving depletes considerably faster but still not terrible as I was able to get approx 65 miles out of a fully charged battery (before REX kicked in) doing 72+ mph on the highways in Phoenix.
Oh - and no issues with reliability so far.
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