In theory, an EV should have less problems (less moving parts in an EV, no oil change, no gearbox etc.) as long as there os no defect with the battery.
On the other hand, many people choose the i3 REX version which adds a traditional engine. Are you going for the BEV or the REX version? The REX version looks a bit more complex but does away with range anxiety for some buyers...
It will be interesting to see the order ratio from i3 pure BEV to Rex over time, here's a discussion with pros and cons on it:
http://insideevs.com/bmw-i3-to-rex-or-not-to-rex/
PS: Thinking long-term, this BEV vs REX decision might also affect the resale value of the car.