Lick my plate!
I skied the first generation Burt also but not more than one season if that. I didn't have any cable issues, just couldn't get past the weight. They were mounted on a pair or Olin Mark IV's and everytime I tried to jump off a bump the tails would drag. Sold them at a ski swap to some younger guy, just because they were not good for me doesn't mean they were not good for someone else.I skied on Burts ( 1st generation ) for a season -mostly for the novelty . I don’t think the concept was bad but there were issues with cables , springs ( I broke one)complexity and weight. A larger company might have had more $ for prototyping and testing prior to launch.
As for Spademans, I competed on Super 2’s and 3’s and had no problems whatsoever and I wouldn’t have any qualms about skiing on a good pair of S4’s now- the design was improved consistently and brilliantly simple. As for friction- well, that’s part of what keeps your boot attached to your binding-pressure = friction . it’s when there is too much friction that problems occur. The actual surface area and the friction coefficients of the Spademan plate/clamp are relatively small and most importantly, directly in line with the tibia, alleviating torque loading.