I installed the Vortech heads with a retro fit HYD. roller cam on my old 350. I used the self-aligning rockers. They are the 1.52's . My lift on the cam is about .480. I installed springs as well. I did not drill out the pushrod hole, nor did I add screw in studs. I have not had any Issues with this set up. It's been over 5 years of daily driving the truck.
They recommend screw in studs when over .500 lift and or higher spring pressures. Alot of this depends on the use of the engine. If you are drag racing, then yes, you should build the valve train for high rpm use. In my old truck it rarely sees over 4k rpm. I will get the spring and push rod info for you if interested.