So i know how a pcv (positive crankcase ventilation) valve works in theory:
limited flow at high vacuum and greater flow as the throttle butterflys more fully open.

I know that as the rings and bores wear blowby gas increases and the pcv may need to changed to a higher flow device. I know that Ford makes a higher flow pcv valve for high mileage v8s.

I have read that somehow the 1994-1995 iron 8L V10 got by with no PCV mechanism, just a fixed sized hole.

I have read that a "Dry Sump" is a kinda pcv replacement... the vacuum pump sucks all the blowby gases away at all rpms and the crank/rods/piston undersides all move with less air to push out of the way. This saves more horsepower at high rpm than the vacuum pump consumes.

I have not thought through how a "big cam" with more than stock overlap affects pcv selection.
Big cam overlaps make idle vacuum lower. Big cams create "internal EGR" at idle making the idle rough and lopey.

What adjustment does it have that makes the custom PCV worth $127 ?