Arguments over the BEST ROCK GUITARIST EVER are usually pretty pointless...but still can get very heated.

Everyone's got their opinion, nothing you say will ever change them, someone's going to annoy everyone by talking about YNGWIE MALMSTEEN, then you all go home.

Well here's a couple who took a "who's the best guitarist?" argument to a whole new level.

Last week, in Brook Park, Ohio, a couple was at a Motel 6 and got into a debate. 

The guy was ADAMANT that SLASH is the best guitarist ever.  His girlfriend was ADAMANT that EDDIE VAN HALEN is the best ever.

The argument got SO LOUD and SO VICIOUS that other people at the Motel 6 called the cops.  So they came and got the couple to agree to quiet down.

But while they were there, they ran the guy and girl's names through their database . . . and found out both had outstanding warrants in other cities. 

So, because of their Slash-versus-Eddie debate, they're now both in jail.