I once put headers on my V10. They even had a 1" flange bolted to the block. They still warped and I always had leaks. Until I bolted the factory ones back on. In my opinion they work the best. Something I was thinking of doing to my V10 is putting in Total Ring Seals. Gap-less piston rings. And like ramvan2500 said "Not many companies bothered making performanceparts
for the V10" so upgraded parts might be really hard to find. Good luck.