You will see better performance gains out of a B-series but some people swear by the D-series. I personally would throw a B18C in there and call it a day. You will get daily driver reliability with about the same HP gains with about the same amount of money as that kit. Then, you can decide to turbo that down the road. I have a GSR, so I am partial to the B-series anyway, so I am just giving my $.02