Which exhaust would be the best deal?

I have a 08 Yamaha fz6 and I'm trying to buy a new exhaust slip-on for it. I've narrowed it down to a M4 carbon fiber, Two Brothers Racing M2 Dual V.A.L.E. or a Scorpion Dual Stainless steel exhaust. The M4 and Two Brothers are close to $700 while the Scorpion is around $500. I;m leaning with the Scorpion since its so much cheaper but I know usually you get what you pay for but I watched vids off youtube and they sound pretty much the same. Does anyone have any advice they can give me? Like is carbon fiber really much better than steel? Any advice is welcome.

Daniel, buy the one you like the most. The difference is only 2C more and after spending 5c what does it matter. Frankly I would leave the bike stock as it is with more stock that in any other configuration.