I run a Comp...solid flat tappet,.620 lift..262/266 @ .050 duration,with 1.6 Crane Ductile rockers,bronze-bushed and gone through by RAS. Isky 8005A springs,145/345 psi. My adjustments stay rock-solid,after initial settings in the Spring. If..and when I ever go to a solid roller..it's either Harland Sharp's or T&D!