I was wondering is a battery tender a good thing to pick up? Im not too sure I live in NJ where we have 4 seasons and its going to be winter soon. I dont have a bike but planning on getting one early January. If anything it would be for later. Im only saying bc the tender jr. is on sale for 25 as opposed to like 40. Any pros btwn 6 and 12 volt bc I have the option for either at the same price. Pls hurry bc the sale is about to end soon!!!