OP asks for "best bang for buck", and there's two responses naming the most expensive rockers you can buy...... Moparts.

I've been running Pro-Comp Steel bushed roller-tip rockers for a few years now, and they still look and work great on my .575 lift solid. Crane Ductile steel rockers are great bang for buck, but above .500 lift, conventional wisdom says use roller tips. Comp Cams Pro-magnums look like solid value.

I'd stay away from aluminum unless you're spending big money. Seen too many budget aluminum rocker bodies break under marginal pressure.