Is anyone running these in your tin? They have more CCA (930) than a Sams Duracell agm (800), but 10 min less reserve cap. than the Sams. They come with a 4 year warranty too, but they are almost $400 a piece. It's time for new batteries, and these would obviously just drop in, to replace the current 27 series I have. While the 31 Duracell would be more of a project.