I give it a 10 out of 10!!
These 2 are my 5th & 6th Endura. It took me a minute to learn the tips & tricks of the Enduras, but I love them so much that these will be back-ups and not even opened until needed. Of the 4 I already have, only 1 has failed and I'm sure it was from overcharging. The first two were red and black and I learned that the stainless are best for me since I tend to put them between my legs while driving, forget it's there and it drops out of the car and chips the paint when it hits the concrete. Duh. Obviously, I give it a 10!!