BMW’s i3 uses a similar system, and in both the i3 and Leaf I’ve found the system unwelcome. I have two objections: firstly, I don’t want to weaken my habit of using the brake pedal to stop as doing so seems potentially dangerous to me; and secondly, I can’t be bothered to relearn how to drive a car smoothly, since lifting off triggers mid-level braking when I’m not expecting it. A colleague also suggested that the increased dexterity demanded of your throttle foot leads to greater leg strain.
I didn’t use the e-Pedal for long enough to verify objection number three, because I switched it off after 10 miles. Thankfully that is something you can do in the Leaf, whereas in the i3 the single-pedal action is a permanent feature. I should also add that most people who’ve tried it seem to like using e-Pedal, so my objections are very much a minority report.