I have power selects-8 on a pair of SX-192, I did this for ice or high speeds so the ski would be more like the SF ( have the speed plate also ,which according to the rep amplifies the action)I did notice a diff , but how much can not be quantified since it is impossible to duplicate the identical line you take. Same thing when I uncambered the ski for bumps.I have a pair of power selects -9 on a pair of G-3 volkls with the speed plate and have not turned on the power select yet , I chose that combo because I could get the plate and binding in fire engine red which looks sick with the puke green of the volkl. But so far have had no desire to try, since the skiis do it all. As far as Tyrolia, they do not make the binding any more and have replaced it with the Rail-Flex.With how skiis have gotten shorter in the last two years , the rail flex makes more sense. The rail flex can be adusted fore or aft by 15mm and is total freeflex(instead of only a freeflex heel)so you can move it forward and be quicker in the moguls and park and just put them on a volkl for that grip.