I have an almost exactly matched pair of Mossberg shotguns (930-935).
One has a ported choke and one has a choke with no ports. I cannot tell the difference between the two as far as recoil.
Interestingly enough the 935 has an oversized barrel diameter to handle magnum loads and takes a different model choke. They both pattern completely differently, but I doubt the ports have anything to do with that...