Smart! I highly recomend the rail gauge so you can dial in the mp-8 perfectly and the fuel psi so your not starving your cp3I just bought an MP-8 but haven't tried it yet. I've been running the Edge EZ for a couple of years on the stock injectors with no problems. I usually keep it on level 1 for daily driving, level 2 occasionally for playing around, and level 3 for the dyno.
I plan on using the mp-8 in a similar way, but I'm not gonna install it until I have fuel and rail pressure gauges installed so I know what's going on.