Whats the difference? All ive ever tried is a single 510 LR atty which I purchased for the intent of dripping and it was rather nice but since then ive only used regular 510 attys. Recently purchased a reo mini and are on the lookout for highdrain batterys since theyre out of stock atm but I do need some LR attys to with the batterys aswell so was just wondering if the difference between 306 and 510 is noticable?