For me the risk isn't in the mode of locomotion. ICE versus Electric motor doesn't concern me so much.
I wouldn’t compare internal combustion engine to the whole electric car. Bad comparison in my mind. Rather the comparison should be apples to apples, meaning compare the ICE to Electric motor.
Electric motors have been around and in development since 1740. Internal combustion engines have been around for nearly as long. But again, these technologies do not, for me, represent the greatest risk.
For me it’s the battery.
Specifically with battery life, longevity, safety and cost of replacement.
After watching
this video of the battery pack being built for the i3, it looks like they could be easily replaced when needed and if newer technology improves on the existing battery.
Safety seems to have been addressed too but with the exception of under-tray impact resistance. I haven't found any information or videos demonstrating the battery packs ability to absorb impacts to the underside of the tray or prevent penetration by road debris. This was a problem with the Tesla and which lead Tesla to provide shielding for their battery packs.
An other risk (for me) involves the financials of the vehicle. Will they hold their value as compared to other comparable vehicles? What will the used market be like for the i3? Because only the original buyer can claim the Tax Credit, used car purchasers may be challenged. How do used Nissan Leaf, Toyota Prius and Tesla S owners doing when selling their cars off? I haven’t really looked into it.