In answer to some of your more specific questions, yes, Crane "Energizer" rockers are "famous" (infamous is more accurate) for NOT being very durable.
Aluminum rockers are known to "work harden". That is, as the aluminum heats up and cools, it changes the sructure of the material over time. It can become brittle. That being said, more modern alloys are much less susceptable (sp?) to that.
For years, Harland Sharpe was THE roller rocker of choce, particularly among those wanting to "spend less". And Pontiac has a "special" relationship with the HS rocker, as it was Pontiac the first ones were designed and produced for, circa 1960.
Scorpion rockers are more rigid than the HS. This gives a more accurate "ratio" when measuring, as there's not nearly as much "deflection" built in. The HS rockers tend to "measure" at about 1.7 or 1.75:1, while actually moving the valve 1.65:1 (or so...). Scorpion is made in USA. It also "fits" under stock covers, for the most part, as well as the HS rockers.
The steel rockers like the aforementioned PRWs, Comp "Pro Magnum" or "Hi Tech" are much stronger, and would be the better choice for a street engine. The Comp offerings, like the Crower stainless rockers, are not "cheap". The PRW is a Chinese "knock-off" of the Comp Pro Magnum. Relax fellas, we sell 'em too!
FWIW
Jim
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