Today i used the preshave oil from SV, and were i am not a very big fan of pre shave oils i like this one because of the roller application, i put on some stripes of oil on the cheeks and massage that in the whiskers.
Sometime in the late 80s I was at Bread & Circus in Houston, TX and stumbled across a very tiny bottle of some sort of shave oil. I used it for a few years after and ended up crafting my own. I no longer use an oil as pre-shave/shave. It clogs up the works.
My preshave back then, as it is still to this day was/continues to be a nylon scrubbing mit with Dr Bronner's soap (these days plain/unscented liquid.)
Since returning to the DE experience I've added PAAs Cube 2.0 (non-menth) following the aforementioned scrub and rinse.
I apply the Cube directly from the block to my beard and then use my fingers to rasie a very dense, slick cloudy sheen. I wouldn't necessarily call it a lather as it is considerably less hydrated than a whipped lather you'd get from a great soap.
I have noticed and pondered, though haven't done, the Cube would/might make for an excellent shave soap in its own right.