I've hunted the last two years off a Predator. I also had the opportunity to try buddies Ridge Runner this last summer. They both excel in their own way. The Predator is slightly lighter and packs slightly thinner and hooks up to the tree well. That said, the Ridge Runner is only slightly larger and really locks to the tree. I was standing with my feet on the "wrong" side of the V shape of the platform pushing it away from the tree and it didn't move a bit. It locks solid. Which is better . . . it's too close to call for me and is going to be up to what you're looking for in a platform.
Personally, at this point I'm sticking with the Predator simply because it packs a little better and I have replaced the strap with an amsteel daisy chain, a mod I think would be difficult with the Ridge Runner given the location of the attachment lugs.