Royal Yaksman
I did a quick and dirty mess with effects pre-sets on a bunch of loops, to create multiple mixes and utilise mix recall. Thus far, it is f-ing sweet!!! I thought it would take a bit longer to swap everything out, but it is surprisingly quick. (Though it may not be the same case for gigantic scoring types???)
It seems Mix Recall's responsiveness depends on how much you've changed in the project. For vocal up/down it's super quick. For changing out bunches of effects, tracks, automation, etc. it takes longer.
Glad you discovered the VocalSync is more than it appears at first. One thing that will confuse people is there is no "more" or "less" with the control...it's not like turning it clockwise syncs more and counter-clockwise syncs less. The "sweet spot" could occur anywhere along the knob's travel.
So it looks like now I will have an endless supply of new topics for Sound on Sound columns...