New valve springs and valves worth it???

[MoNsTaMaCk24]

I thought about going with different valve springs and stainless steel valves for these P&P PI heads... Thing is I only paid 850 shipped and they came with SHM blower cams and they are stage 3 P&P but come with stock valves and valve springs but it all only has 800 miles on them. I saw that new post of a guy getting over 600 rwhp with stock heads and intake... With a supercharger... I am thinking about a turbo kit... So let me know..