Only you can answer that. For me, I am glad I have it, as I like to monitor things, as well as what gear I am in. I went to the east coast and towed a trailer back to the west. My trailer lights would appear disconected at times, as the dic would read sometimes. After looking on the internet trying to figure out why, it was confirmed by the voltage gauge I had. I would have only been guessing without the gauge. When towing, alot of times you think you are in 10th gear, but you are not at times. I like knowing, but probably not necessary.