I have had a few sets of those rockers. Both 1.5 and 1.6's. The last set that I used was on a 440 with a small roller cam with 240 on the seat and 600 open. I drove that car 35 miles to a car show and 35 back a few times, a summer of drag racing and putting around town and the only issue was that there was scuffing on the bottom of the shafts. When I freshened the engine for the guy that bought that car I noticed this so we installed new hard chrome shafts and let it go. The engine has only been on the Dyno since but it seems fine.