Maybe Colby could take RDA down on a couple times, but I highly doubt it will be enough to win. Everywhere else RDA is better.
That literally leaves the feet.
He just beat and controled Maia on the ground, do you actually think RDA is a step up or down from that??
Watch RDA vs Clay Guida
And RDA vs Khabib
Stylistically Colby is a nightmare match up for RDA