I think it comes down to a few differences: 1) $$$$$$$ 2) Stock look that is hand made vs a cool modified looking piece that comes in your choice of colors and is machined made. 3) Other mods (the Needswings bigger tanks "might" come into play and be an advantage for a heavily modified car)

I don't know about #3, but it seems to make sense. I'm already on the list for the NW ones, but I think both are good options. I know some people prefer to keep a stock "stealth" look. I'm not in that group. And from a personal opinion, I just think more research and testing went into the NW manifolds, which is worth the money to me.