I have had the 26" barrel w/no ports, very accurate. I have the 20" Katadin barrel w/ports. I'd say don't bother, never had a problem with 777 ffg, very accurate also, but loud. The slight recoil reduction does not seem worth the extra noise. Muzzle rise with the longer barrels is not really an issue for me, so, again I would not opt for the extra work for that aspect either.
By the way, unless you absolutley need the flatest trajectory possible, you may want to try 50-70g of 777 ffg. I load a 335g .452" LBT Hardcast bullet on top of 55g for 1250fps or so out of the 20" tube, plenty flat for 100+yds. Doubt you'd find an animal that would hold on to that slug.
If you like it buy it. If I was a little more daring, I'd have my barrel cut where the ports began to delete them.