The 2Face is to be worn for which ever your preferred stance, but can't slide to both hips i.e. if you ride waves both regular and goofy. So you attach the solder bar according to regular or goofy,flip it 180 degrees and once it's set up that's how it's to be worn. Very few people actually ride waves both regular and goofy, maybe on a tt but not on a true directional.
The Dynabar does have the advantage of pulling either side plus also has other options like the fixed hook and ss slider bar etc on the latest XT models.
We have sold a lot of Dynabars and recently we've also started selling the 2Face but not had any feedback yet and I've not had a chance to try it yet either as still have another week with my leg in a cast!!
I've tried it on though and it certainly feels like it will work.