Vacuum Advance

So,,,,,,,,,,,,,,,,I have a question concerning the distributor on my '70 340 Dart. It has an MSD Digital ignition,,,,, but,,, on the distributor,,, there is a vacuum advance dash-pot on it. Mine is not hooked up to engine vacuum,it was not hooked up when I got the car,,, I have seen guys go either way with the vac. advance,,,,,, for a Dodge 340,,,,, should it be hooked up for better all-a-round performance