Solar: To Ground the panels or NOT to ground the panels?

I had a Renogy tech tell me it's not necessary, and an exhaustive search of the Internet has turned up a few people saying you're stupid if you DO and others saying you're stupid if you DON'T.

I've searched these forums, and either didn't search correctly, or there's not a lot here.

What's the consensus?

I'm installing 6, 160w Renogy panels, into a Midnite combiner box (circuit breakers / parallel).

Thanks