Would be an awesome fight. I'd take Gus but Rumble could do well. Jimi Manuwa tagged Gus solid a couple of times, and I think Rumble has the more diverse striking, and his grappling is also not a weakness like Manuwa's grappling was.
AK's, AR's, aye y'all, duck.
I shouldn't have to put "imo" at the end of all my posts for you to know that I'm giving an opinion, not acting like my thoughts are facts.