Benzino says the bad outweighs the good when it comes to 50 Cent's track record in hip hop ... claiming when you talk "just the facts," the facts aren't great for Fiddy.

The former "Love & Hip Hop" star is the latest guest on the "It's Tricky With Raquel Harper" podcast, and he's addressing his 50 Cent beef head-on by strongly hinting he's about to drop a lawsuit on him and several others.

Then Benzino, who was co-owner of The Source, rips his nemesis, saying ... "He's the first 6ix9ine. Like, the first hip hop rat!!!"

As you know Tekashi 6ix9ine infamously snitched to the feds on fellow gang members to get a reduced sentence -- and Benzino's referencing an old allegation Fif ratted on former record exec Jimmy Henchman.

Benzino even references federal "paperwork" allegedly signed by 50 that would prove he snitched -- a claim often repeated by Ja Rule and others at Murder Inc. Records.

However, 50 Cent's always denied this, and as TMZ first reported ... law enforcement sources told us those documents were fake.

Here's the odd part ... Benzino reminded Raq he went out of his way, back in 2000, to help 50 -- and possibly save his life -- when he got stabbed at Hit Factory studios.

Clearly, things have gone way south between them since then, and Benzino's not backing down.