MSD -vs- Jacobs

I currently have a Mopar electronic dizzy, (adjustable vacuum can), Mopar orange box, Accel supercoil (big yellow thing) and I yellow accel plug wires. Cap and rotor are probably Echlin from Napa. I'm looking for a little increase in mileage... as a daily driver, if I can squeeze a bit more MPG out of it, it keeps the wife happy!