I have been using Sack-Ups for years for my overlarge straight razor collection. I use all my razors, some more frequently than others. I mostly own the 6" pouches, but now that the 7" are available I have shifted all my larger/longer SRs into those. I have had zero corrosion problems.
My razors are kept laying flat in a large wooden flat file case. I lined the drawers with thin plastic sheeting.
I've got a knife collection of around 1200 knives. 900 are old slipjoints.I keep them in your sacups. Ive used them for at least 20 years. I gave always gotten them a SMKWs but they don't seem to have them now.
I have many of my firearms stored in sackups. The guns stay clean and dry. sackups construction is high quality and provide great protection. The 10" model is fine for smaller pistols and larger sizes work well for other guns. Great product, I will purchase more.
On the thin side and difficult to put over the AR