
Originally Posted by
theveed
They're not a necessity at all, as with ALL aftermarket parts.
You won't really improve on anything if your car is relatively new and stock. If you start upgrading other things like ignition, audio, etc, then your system will be able to function a little more efficient since it compensates for the additional load to the electrical system.
But the "correct" way of doing it is to upgrade your alternator to match the needs of your new power sapping upgrades along with a larger battery.