Edelbrock RPM vs. E street vs. Stealth?

Hey to all the knowledgeable folks on here, in anticipation of building up a 383 for my Scamp, I went about reading on available aftermarket heads and found the usual items; Stealth and Edelbrock.

From what I could absorb on all the commentary for the Stealths, the first versions were lackluster in fit/finish and had tendency to crack and the retainers sucked. The later versions were much better, but still lacked good locks/retainers and left some to be desired when it comes to port/bowl cleanup. In a nutshell, not a bad head, if you're willing to shell out about $80 for some new locks and retainers, and break out the die grinder with some sanding rolls for about 20 minutes to cleanup those areas yourself.

From the Edelbrock side of the house, the ones I looked at were the RPM and the E street offerings. I really couldn't tell any significant difference between the two apart from combustion chamber sizes, to include part number 5090 (75cc) which isn't even available yet. Unless I missed something they both have 2.14/1.81 valves, are available with 84cc chambers, up to .600" lift cams, port sizes 210/70cc, etc etc. The only big difference I noticed from description and pictures was the 88cc chamber with the .100" relief cut for dome pistons.

I also noticed from Jeg's description, the E street heads say you can't use a hydraulic roller cam with them, but the RPMs have no such limitation documented. I like the idea of running a Lunati Voodoo 270/278 HR cam in my build, but why would the E streets not be compatible, and the RPMs are? Is it because of the springs?

Any ideas?