Dont know for a fact who makes the batteries,someone told me it was westco. Megaboost is a Cyclegear brand.Their 100% satisfaction guarantee is truly a 100% satisfaction guarantee. Never any issues returning something I wasn't happy with.The warranty is all over the box and the website. I read mixed reviews on the megaboost battery(I think that goes for any battery) but nobody had problems getting them replaced.Cyclegear are good people to deal with.
I would guess that the batteries are a loss leader to get you in the store. I wonder how many do get returned? People dont seem to keep their bikes that long,so probably not many.
