[blykins]

True, the Ersons will hit the studs, but it's very easy to make them clear. I used Ersons with ARP studs on my 428. Just about 2 minutes with a little grinder bit and they cleared just fine. It doesn't take much at all to make them fit.

You could ask some of the high volume builders which rockers they use and what they've had the least amount of trouble out of. I think KC uses Erson and T&D.