I agree with Cr0 Reps. They are all good and well established for park riding. Go with what you want. I personally like Union best of the ones you named, I liked the Data binding that I rode. I personally ride Burton Cartels for the weight:strength ratio. I like a light weight binding and don't expect them to last more than three seasons.. But I do expect them to hold up to harsh wear for at least 2 seasons without deminishing performance. I know Unions are really tough and I liked their straps, ratchets and fit as much as Burton. I would prefer most Union stuff to most Burton bindings if I didn't always get a great deal on Triads and Cartels. But like I said those are all good bindings
If you have a boot you like best, maybe take it to some shops and see which binding fits your boot heal nicely. And then you'll get a feel for how you like the straps and ratchets.