I've found the latex from Pioneer to be the easiest to work with in terms of stacking and tacking layers because it has the talcum powder and slides around a little easier. I like the latex from Mitchell at Dead End, but it's a little trickier to work with because it doesn't have the talcum and tends to stick together when moving around to stack and tack.
But for proph, I haven't found a good solution. It just slides all over the place and seems to be impossible to tack down after stacking. What is the best method to keep proph in place before throwing it on the press?