My first Shield was a PC .40. I wanted that caliber first as my FS M&P is in .40 as well.
Then I got a .45 Shield, and now, a 9mm.
The 9mm will be given to my daughter soon.
I'm shooting it for a few weeks, have ordered a TRL-6 for hers and holsters to fit them.
I imagine a standard Shield in .40 would be a handful, with the porting, mine is pretty enjoyable to shoot.
It has some recoil and muzzle rise, but is much closer to my 9mm than my FS .40.
I went to the range three times to shoot the .40 PC and .45 Shield's side by side, and each time I clearly liked the .40 PC better.
There are a lot of guys out there that love their .45 Shields, maybe the PC model spoiled me.
I believe, whether you get a PC model in 9mm, .40 or .45, they will have a nice out of the box trigger, and the porting does help.
Less recoil, and we all shoot better with a mild caliber than a bear crusher.
Less muzzle rise, so you get back on target quicker.
Too much velocity loss ? Too hard to clean ? Too much flash out of the ports at night ?
I've chronographed the PC, shot it after dark, and have to take maybe an extra four or five seconds when cleaning to wipe the carbon soot around the ports and inside the slide where the gas jets up.
I wish some of these guys that badmouth the barrel porting, would actually get a PC Shield and do some testing before proclaiming the ports worthless or more trouble than they're worth. Maybe they're just jealous.