Cobrarkc Rich I think PRW makes Shelby rocker arms. Not 100% sure. Here's the thing, You are paying about 20% more for the same rockers because of the LOGO. You gave no specs on the motor. Size of camshaft lift, valve spring close and open pressure, max rpms looking to turn. Over build the motor, YES. You didn't say which rocker you are looking at? Stainless steel or Aluminum. Bushing or bearing pivot?
Heres the best and working down, Jesel and T&D. None better, down side machine work may need to be done to heads for installation. Harland/Sharp company been around for 50+years. Believe they build in house. You have Crower and Isky after this with PRW. Can't answer you on Scorpions, Proform, Summit, jegs, or Comp. I think Dove etches there logo on the rocker they make and sends them out in bulk. I have seen this visiting Dove.
Which ever rocker you go with do a test for the correct pushrod length and centering the rocker on the the valve stem. Smith Brothers will make pushrods to any spec and have a 72 hour turn around. Top maker, have run 3 sets in different motors. Work great.
You left out 1 thing, oiling system, any modes done, HVHP
oil pump. LImiters in the system, extra
oil supply lines internal? Per oiler? Larger
oil pan 7-8 quarts. All this is important too. Per oiler and running an oil suppliment with clinging agent to stop dry startups. Little more info would help. Rick L.