"I work for a scientific agency, and we use Optima batteries exclusively now for our field equipment. These things are indestructible, and just keep giving. We've had 6 of these batteries purchased here, and are adding to the collection. These will run (in pairs) all day charging capacitors which dump six-hundred amp pulses. After 3 years with those, I've not noticed any reduction in capacity. We've all changed our personal vehicle batteries to Optima now."