Groo here
I have a few magna-ported guns from 357 to 454 revolvers
and TC's.
On an SSK handcannon it is about required,
on the FA 454 it is most welcome [I have cut my hand on the frame
lumps of single actions]
on 44mag I find that I don't needed it on longer barrels
but on my 3in Trailboss it works very well.
and on 357's --works wonders on an SP-101 2 1/4 in [4 port] I set this up to be a hunting
backup gun and have shot 200 gr monster loads from it- heavy but boy do the drill deep!
The thing is that it will do little for the kick, the big thing is the rotation.
Ps, this is with magnum /full power loads, the light stuff
just does not need it....
PPS As an old revolver shooter I never had a problem with the noise,blast or hip shooting
drills as some have because the blast from the BC gap is so big with magnums that
any change the porting might cause is not a factor-- even at night
we even used the flash to help sight the target at night for followup shots...