I installed the Hughes 1550 rockers arms on a set of Engine Quest heads about 10 yrs and 10k miles ago, no problems so far. I think they are basically Chevy rockers on adapter studs.
The only odd part was very little thread engagement on the adjusters. I called Hughes, he said it's normal and hasn't casued any problems. No problems so far with mine, I don't really rev it past 5500 RPM.
https://www.hughesengines.com/Index...a2VyIEFybXMgJiBBY2Nlc3Nvcmllcw==&partid=25405