I swear by them. Had a set in my old 340. I used the Direct Connection adjusters & nuts. The 340 had triple valve springs, a .585 lift solid cam, 13:1 compression & a 7800 rpm shift point. Never broke a rocker, bent a lot of pushrods though.
My current 273 has a .551 / .531 lift cam & I'm using the original to the motor, redressed rockers with ARP adjusters
