I have been using the Nissan-provided EVSE for 11
months, and only had one (recurring) problem:
I occasionally forget to plug it into the car!
Not only perfect performance, but charges twice as fast
(on 240v) due to Ingineer's nicely-done upgrade.
Further, I am about to get and try his "Rev2" (12 amps
to 16 amps) upgrade (though I do wish it was switchable).