I have used both Megacycle and Web hardwelded cams. The only problem I've encountered is a reduced base circle which can cause a problem with shim/bucket arrangements (if you are near the end of the thick shim range to begin with). I would use used rocker arms but they would have to be in excellent condition. New rockers or, better yet, hardwelded would be the most desireable set up. The hardwelded Megacycle rockers are real nice but very expensive.