For what you're building I'd rate them this way in terms of cost vs reward vs room to grow:
1) Edelbrock RPMs (LA closed chamber) - good for current build, closed chamber, light weight, reasonable cost with correcting the valve job, uses any rockers, plenty of room to grow should you decide to go faster.
2) RHS heads (IMM would get the knod given your location) - Good for the current build, closed chamber, heavy as hell, reasonable cost, rockers are more expensive, porting further is expensive and there is little to gain with it because they are that good out of the box.
3) Ported X heads. Works with what you have, needs little to work really well, no initial cost, assumes they need a performance valve job, bigger valves, etc etc, less room to grow, heavy, open chamber.
4) Procomp heads. IMO - way too much for what you're doing. lots of room to grow, closed chamber, light weight, but too much port for the current build.
