anders_aI have shift, duke pt 16, and CAST
shift, superlight, very large BSL adjustability, kinda fragile, I use them on light skis, like pescado, BC120, bibby pro
duke pt 16,on heavier skis kinda a fattie, but also some skis I ski park and misc but wanna be able to use different boots, have it on revolt 121, fischer 102 FR etc 60mm!!! bsl adjustment best in class by a mile, you can borrow to all your friends.
CAST = heavy as fuck, indestrucable, 0 adjustability pretty much, your stuck at same shellsize +- mm , have inserts, so I can use it on all my skis, meaning park skis, and also blackops 98, 118 and misc. when weight is not an issue
I have to many bad memories from frame bindings to like them.
^This is a pretty good summary.
But I think it depends on the skier more than anything. I'm a pretty light guy, and I have had 0 problems with the Shifts. The Shift is the only binding I'd consider on a ski I was planning to tour regularly (or far) on because the weight saving vs CAST or Duke PT is massive.
The way I see it is that the Shift competes more with the Kingpin and some of the more heavy duty pin bindings, and to me it's far superior. Meanwhile CAST/Duke PT/Daymaker more or less eliminate the reason for frame bindings to exist.
For touring often/far, I'd use shifts and I'm comfortable enough on them that I can hit jumps and butter around without worrying about reliability. I do still prefer regular bindings for resort use even if that's just a mental thing.
For mostly resort with occasional short tours, I'd honestly just use Daymakers. They have downsides for sure, they're fiddlier to change from tour to ski and they do mean you're touring with a huge stack height, even compared to frames, which is rough on traverses. But if it's not a regular thing they will get you there and the touring motion is way less of a hip killer than frames. They're also cheap and you can use them on all your skis.
For bigger people, or people charging really hard on their touring skis, I can see why the PT and CAST appeal. CAST still seems to be the preferred option but both have advantages and disadvantages. Personally, I would definitely not want the weight of either of these on a ski I ride regularly inbounds or tour lots of vert on. But plenty of people do it.