Variable hydraulic lifters for 440 engine

I can try and ramp up the idle to 900, just by turning the initial advance to 18*-ish.
First i will check again on the intake to see for leaks, after i can play around with some settings and see what it does.
If a am still not happy i will consider the variable lifters to install, so from what i read is that the Rhoads are the best right?
You can actually set them where you want as where the Huge Engines seem not adjustable in that way.