Anyone using an external battery to supplement the internat battery on long rides. If I understand correctly something like the Energi To Go battery can be used? I was wondering what the experience has been, how much it extends the usage of the battery, etc.

Also, I purchased mine used and it only came with the USB cable. Does the A/C charger do any better charging to maximum capacity?

I purchased a refurbished unit that had not been used. I have not tested it on a ride longer than two hours. Since it does not have a battery level indicator I have no way of knowing the capacity but it does not seem like it will last as long as advertised.