Hey guys,
I’ve been wondering if there’s one that’s actually better than another. Say you would have a primary USX / DSX and only switch on that final stroke temporarily for that specific stroke to the other motion, or would being able to play whole bars depending on which ones required more better?
The better one is the one that’s easiest for you to do.
Dabble in both and then you can experiment with what feels the most natural in any given situation, why limit yourself? 
The terminology is updated now. “Two-way pickslanting” is now thought of as just a ‘helper’ motion when needed to make a different escape. Troy found in practice that an all out change of slant was rarely needed/used. Instead, people made these subtle movements to help assist with the other escape motion when needed. Examples would be like Andy Wood or MAB. They may show a primary DSX but occasionally need USX for a note here or there. There is a better explanation here:
“Two-way pickslanting” is now reserved for players like Frank Gambale who actually change their slant mid phrase due to economy or sweep picking.
Couldn’t agree more! I think it’s important to remember that most of the awesome players we see developed their techniques pretty organically. That’s why most of them have different strengths.
It really depends on how you pick, what joints you use, what phrase you are trying to play etc etc
Have a look at what @joebegly linked and you’ll see how players who play using wrist, forearm and wrist, elbow etc manage those string changes.
Once you have that understanding then it’s a case of trial and error. Try it at speed and see and feel what happens.
If you have a good single escape technique already, it’s a little easier to try it at speed and see what happens. You can then slow it down a little and gain control of it.
It can be one of those things that is harder, initially, to figure out if trying it slowly.
Well not to mention that at super high speeds most people just abandon any kind of two way escape and go for swiping. ‘Cause really, ain’t nobody got time for that.
I swipe all day long 
Is there an, all three option?