Installed MSD Ignition on my Z

I was in advanced auto yesterday and saw that they now carried MSD street fire products. I decided to try the Street Fire CDI box (PN5520) along with an MSD plug and play harness (PN8877) since its smaller than a 6 series box and it has built in dials for the rev limiter (which the pcm controls anyway). It might add 3-5hp at most but I have noticed that the engine idles smoother and throttle response has increased slightly, even with the stock coil. Hoping for a slight increase in mpg.

http://img517.imageshack.us/img517/7017/dsc05074mk8.jpg