Porting--Boo, hiss!
IMX, porting of any sort is the worst favor you can do to all the other people who shoot at the range with you--they get all the extra benefit of your enhanced noise and muzzle blast. It's a good way to not make friends, especially on a firearm that is on the loud side anyhow.
The ports collect crud and have to be cleaned. I had a revolver once that was ported. The bbl leaded in that revolver, and of course the ports leaded up something fierce and were a beast to clean.
Keeping the muzzle down in a pistol means that you absorb that much more of the pistol's recoil with yr hand, arm, shoulder, and back. I fail to see a benefit there.
If you "need" the ports for recoil control, because you're practicing with lots and lots of full-house rounds, IMHO, you're wasting powder with yr practice. Practice with light loads, much cheaper, easier on yr gun, easier on you, you can get much more practice in and it will enhance yr skills more because you don't get pounded by the recoil.
In all fairness: Positive things abt. ports: The Wby BOSS system is supposed to enhance accuracy. Anything that enhances accuracy meets with my approval. (But, the BOSS can be had with or without the porting!) Plus, ports certainly enhance the tacti-coolness of even the humblest of hunting rifles, to say nothing of the "sniper" variety.
Do you get the idea that I think that porting of any sort is a waste of time and money?