I bought some skyback cartels from broke_folk and I feel like forces are the closest in response/stiffness but, in my opinion, more comfy in the highback area. Atlases to me are more comfortable than the force but have more lateral flex and a "torsionally" softer highback. I didn't really notice a difference in response straight back.
@Vaya,TLDNR [Atlas, Contact Pro, DK, or just keep your forces, you can't go wrong with either]
Vaya, How stiff of a rocker are you looking to buy?
If it's on the medium side, I'd say you should lean atlas, which is my favorite binding in the line. It feels like it will be what you want it to be. If you want to press and try ground tricks, it'll be soft for you, if you want response straight back while making a turn, it's there too.
If it's on the n00dle side, I say lean contact pro. I ran some contact pr0s on my arbor draft and liked them way more than my contacts.
Another choice to consider is the Danny Kass binding. Haven't ridden them, but kinda want to buy some. It's based on the Flite, which I liked but thought the highback was REALLY soft. This one is carbon injected and has a team highback which, if it's anything like the Atlas highback is nice and responsive.
@Shralp, how would you compare your SLs to your contact pros?