This forum pumps Flux a lot, with a lot of people using them who approve. All I can say is what I saw with my eyes.... They seriously looked to be made for children.
Rome 390 are time tested and known to have arguably the most comfortable ankle strap on the market. The footbed isn't cush like k2 though
Union Force is a virtually bomb proof binding that really doesn't do any one thing exceptionally well, or is exceptionally comfy, but it's a binding that does everything.
I recently checked out the k2 Auto Uprise and fell in love. However, it's not a park specific binding.
The footbed has an industry leading comfort level. The ankle strap is very very close to being as comfy as the 390. The toe strap is nothing short of amazing. The ratchets are also very smooth.
I personally think the k2 Auto Uprise has raised the bar as long as they stand the test of time. They have incorporated pretty much everything strongly desired in a binding.
Oh and the auto strap system has been shown to stand the test of time, which was the major concern with these bindings.
If anything, try and go peep some bindings yourself, or hit a demo day. You can read till your blue in the face, but peeping the binding will seal the deal. I was super sketch on the k2 bindings until I saw them in person. They're very legit..
"When I do good, I feel good; when I do bad, I feel bad. Thatís my religion." - Abraham Lincoln
Moral of the story: If your going to rob people, wear a diaper.