roller rockers and solid roller lifters

The build up will be a 440 stroked out to 512 tunnel ram with a pair of demon 750( yes this is a bit excessive, but its what i have and beside it looks really cool) fender wall headers, 3500 stall, gears are 4.10 and the exhaust is 3 inch I'm wanting about 600 HP, I dont know what "bushed the lifter bores means, I'm still learning about some of this"

As for new rockers or not I dont have a preference as long as they are in good shape and not take a dump a month after I install them.