Bad galling on the shaft, the rockers would loosen up between lashes constantly. So after speaking to hughes they referred me to a place that would bush my rocker arms which should have cured the problem but only was a bandaid fix that lasted a short period. The money I spent on the Hughes I should have got off my wallet and bought the Harland sharps right off as they have been trouble free since I put them on.
If your running any hyd or a small solid cam i'm sure you wouldn't run into the problems. Being boosted and probably making the most power on a set of victor heads in the world (good bet?) the rockers get taxed pretty hard. Tho predator heads are my next purchase.

I have a nice used set of Hughes rockers for cheap if you'd like..