TBH I dont know, as for the mileage etc I did my utmost to get the most from them and found it very hard to get anything like 60miles from it, I've been driving Road EV's for 15 or so years so really do know how to get the best from batteries, I need to go back to ECC really and put the question to them to find out if they have "turned down " the BMS to save the batteries from numpty drivers
Dont get me wrong the EVie is a great little car, I think I had hoped for just a little more and when companys put range claims that arnt actually real range claims I think this does more damage to EV's than if they said it will only do 40miles but you might get 50 or 60 from it.
I cant offer any advice on the C Zero I'm afraid as I've not played with one
ChrisB