All of our answers are just going to be personal preference. The actual "science" has little to offer. After seeing Bob Mulden hit small party balloons at 200 yards with a 2" .38 Special, it pretty well convinced me it's the shooter, not the gun that is the biggest factor. It just comes down to what do you want to carry, and what looks good to you. Magnaport may have something cosmetic to offer that really appeals to you, and if so, go for it. I only have one ported gun, and it came that way from the factory. There really isn't any need for it in a hunting gun, but some folks like it, so Magnaport stays in business, and everyone is happy! The length . . . again, what do you want to carry? The guns I hunt with range from 4" to 7.5". They're all gonna work. You can always go 6" and be in the middle. Not too short, not too long.
Let us know what you decide.