the trouble is battery's only get worse with age and more use, also cold weather effects them big time reduces the stored outputs, on top of this testing these products ie car makers set the mileage per charge based on a perfect track low friction road surfaces and on days with no wind etc, where real life is not like that hence why cars never do what they say to the gallon or kilowatt ,, dont think i have met anyone yet that has said they were happy with range and all that extra cost to buy them,, the new golf might change all that if vw can be believed hmmm they never done well with emissions scandal