Big block Chevy build

Well having sold my DRCE stuff I am going a more conventional route. What do you think about Big Duke heads on a 4.500 bore x 4.250 stroke blower motor and if kept under 8k would stainless valves be fine?

 

I use them on big chief heads for same combination, but you need to cycle them as they will tulip over time.

 

I ordered a bare set today, Is there a brand you trust more than the others?

 

I ran manleys and ferreas in my conventional big blocks at 8400. Exhaust valves would start leaking in 20 passes on a conservative tuneup or maybe 5 if I leaned on it. I had all 8 exhaust valves leaking a bunch with 2 at 100% one time. Changed valves, valve job, good leak down and the car ran within .01 of the previous pass.