Why do I need adjustable rockers?
Does the lifter preload need to be more accurate? (.030"+- 0.10" not good enough).
Do they need regular adjustment? (and thus defeat the porpose of a hydraulic lifter).
Adjustable rockers dont need the oil? (that the anti-pump up lifters bleed away).

Bottom Line
Could you, or would you use these on a stock-ish engine.

Chrisp