This will also allow you to tell if you are overcharging. It will also measure your batteries efficiency so you will know when to replace a dying battery before total failure sets in. To a certain extent this boils down to personal preference. If you already have a computer, and use it for other things, then the balance is tipped in favor of the computer. If you are not computer literate, or would like to leave your work behind when you go sailing, then a chartplotter might be better for you.
Computers have the advantage of displaying color charts that are digital copies of the paper ones.
They can superimpose tides and currents. They often have larger screens, usually in color and offer more options and more help than chartplotters. Computers don't work well if they fall off the table or get soaked by a wave. Chartplotters are more robust, designed to take the pounding and soaking that they will get from time to time. They are simpler to use and setup for those not familiar with computers.