sds will be better ultimately for more power and what not, but youll lose conveniences usually. it's also not going to be nearly as clean as nissdata. nissdata is a much betteer solution for a street car. for a race car i think sds could get you the job done a little bit better, because youre only interested in one wide open throttle powerband, and sds lets you fine tuneit much much much more. if i had an sr / ca i would do nissdata without asking questions. and come on, it's much less than $1200 for sds!