I shave them occasionally, but it's more a trim than a shave, I don't stress about getting them absolutely smooth. It's a job that can't be rushed - and NEVER let anyone else try doing it for you.
Some guys like their partners to have lots of hair on their nuts and elsewhere, others prefer it smooth, so as Rick Nelson sang, "You can't please everyone, so you got to please yourself". Certinly I prefer the feel of a hairless testicle on my tongue or in my mouth. However, a few hairs have the advantage that they can be used to stimulate the other guy sexually by pulling on them gently.
As a matter of fact I used this technique on myself just a moment ago as I was typing, and my dick rose as expected.