Looking for battery suggestions. Right now I'm using a Spinner on a Unitank. Everything works okay, but I'm starting to have problems with the threads on the Spinner. It would be nice to be able to get replacement parts for it but I don't think they are available, so I'm looking for something like the Spinner, but with parts that can be replaced when needed. Any ideas? I choose the spinner because I could change the voltage, the reviews were mostly all positive, and it had a good price. It seems like a good battery, I was just to rough on it.