[Mikeod]

With the one Redwitch describes the risk of overfilling is minimized if you don't squeeze the ball hard. As soon as you feel resistance, stop. My first cart had the fill system and they extended the warranty on the batteries because of it. When I got rid of the cart after a few years, the batteries were still in great shape. I think if the fill systems were a problem, they wouldn't extend the battery warranty.