I played a little bit with it yesterday, but found it difficult to get into the position, though when I did, the position felt really powerful even though I failed to make anything out of it (but I was going against better guys...) I'm so used to go in deep for the lockdown when in half-guard. I suppose one entry is to go for the z guard first and then switch while controlling the collar, but that's when I found them standing up on me, so I just have to play with it some more.