I don't know if they are sold by anyone else, but Sarco, Inc., uses the brand name "Roto" for the more or less house brand barrels they sell. I have used several of them and I've been more than satisfied, but none of mine have reached a high round count.
Last night I was directed to a web site where some self-declared expert decreed that Roto barrels are made of "butter" steel. I thought this was interesting, since I had just read an article in a gunsmithing trade magazine that spoke highly of them, and recommended them.
Has anyone else had experience using Roto barrels? If so, what are your opinions?