I was at tractor supply this past weekend, and they have low mantence (screw capped) tractor batteries that have 6 cells (12V) and are about the same size as the golf cart batteries. I looked at them and they are supposed to be vibration protected (yada yada yada). They were listed as 3T size if I remember correctly. So has anyone ever used these as house batteries? Having a smaller boat, I am just looking to upgrade one of my 24's to something like this to give me that extra couple of amps over night. BTW these were only $73 per.