Cast 273 rockers or factory steel rockers budget 360?

... I like to be able to set the preload at 1/8 turn. A 1/4 turn for just driving around.

I do also, but typically if it is general high performance, I use shims. They get me close enough for a hydraulic cam, and as you know, it makes a difference. But I personally don't run hydraulic cams. It all depends on what you are up for, how we spend our time, and what is the benefit. Racing is another ball game, and I rarely give an opinion on that forum.