Generation IV External Engine - ls3 heads- valve choices

can i get away with using the stock hollow stem ls3 valves that come in the heads or should i upgrade them to stainless steel?

Stockers are great.

Heres another question, (dont mean to thread jack). What about the SOLID stem valves in the 823 heads? I know they are heavier, but will the extra weight effect high rpm valve train events at all? Thanks, Eric L