If you have confidence in them go for it. I have used them with good success. I shoot 3" #2 and have shot geese dead at 30 yards on a handful of occasions. Since I mostly duck hunt and see geese as targets of opportunity it is kind of nice. That being said I was not able to justify the price last year and will not be able to do so again this year, so I will continue to shoot Kent shells.
As far as choke tubes go I don't have enough experience to help you out a whole lot there. My brother shoots with a pattern master choke tube and loves it. Just remember that because of the placement of the wad in the Blackcloud shells they can not be used in wad retention style choke tubes, like the patten master.