Hey Kie! Kinda depends on what you're using it for. If you have burly boots and enjoy skiing powder primarily then the 173cm would be my first choice, but it'll be long for steep skiing. If it's primarily going to be a spring ski for steep skiing, you are a beginner skier, or just like skiing in lighter boots then the 163cm makes a lot more sense.
Hey Katie! Kinda, but in an apples to oranges kind of a way. The Tecton is much burlier and functions even closer to an alpine binding than the Rotation 10 does. The Tecton definitely has a resort bias to it. Send me an email at help@skimo.co if you have any further questions and we can get to the bottom of this!
Hey Katie! Ha, dang, sorry if I didn't answer your question appropriately the first time! For primarily resort use I'd definitely recommend the ST Rotation 10 because of the extra release technology and DIN Certification thrown in. It acts much more like an alpine binding on the way down while still having all the touring benefits of a tech binding.
Hey Katie! The Rotation 10 is an upgraded binding by about two generations worth of technology. They're designed to occupy the same place in Dynafit's lineup but the ST Rotation 10 packs a whole lot more technology (and weight) than the Radical ST does. I think for straightforward backcountry with very limited or no resort use the Radical ST is way more than adequate and the ST Rotation 10 is a good choice as well but only worth it if you need the added features that come with it.
Hey Joe! I'm assuming a lot here but it sounds like you have a Dynafit Radical ST (not the Radical ST 2.0 or ST Rotation 10 though, correct?) and you are looking to mount some bindings beyond the current mounting area because the ski has been mounted too many times? If I didn't get that right, send me an email or give me a phone call to reply because I really want to make sure we're on the same page with this complicated issue. If I understood that correctly the first time then you will likely want one of...