I am also interested in this PROMAG magazines for R 597. It looks sleek compared to the 30-rd Remington OEM version. I saw some postings in other forum that PROMAG magazines are jamomatic. But those were posted at least a year ago. They recently came up with Marlin 795 mags and looks promising. Maybe these issues were addressed by PROMAG. Any idea when this PROMAG R597 magazine will be available to canucks? Otherwise, I might have to stick with the shorter double stacked Remington 597 OEM 10-rounders. Mount it stacked on both ends, and it will be good to go. Just spray-paint with black or even a heat resistant black paint and it will look better.