In my opinion, a port hole helps indicate to the sound guy where to put the microphone, lol. More than a sonic influence, a port hole will cause a different feel in pedal rebound. I really believe though that with practice, the correct beater and the tightness of the batter head, the rebound issue can easily be overcome. I have a couple of 22" bass drum resonant heads with small 4" holes burnt into them, but they always sit in their boxes because I prefer the sound of an unported drum.
If you port the head and don't care for its sound and feel, $40 will rectify the situation.