I just got the car back from the mechanic. I had a problem with intermittent electrical issues (the 12v system, not the electric drive). For some reason, brake lights and turn signals were getting confused and not working. Turns out it was a the ground connection for the main wiring harness being rusty and not connecting properly.
My advice to you: convert the latest car you can.
A coworker’s advice: convert the largest car you can (she has a Kewet – tiny little thing). 🙂