Not so long, as in, a month or two. Cosmic and jiminks put me onto Daughters and Ryan's Two Timer, which is two twice-toasted burleys. I bought a pound and shared a baggie with a pipe friend with extensive years of experience, who complained it was over-toasted, but I find it a pleasing burley, toasty but tasty to me. My one big success sharing with my friend was thick cut Tabac-Manil Semois, which he immediately liked. Long ago I sent him a few premium tins, among them 1792 ... on which he never commented at all ... I didn't realize at the time what a specialty item it was, nor how polarizing.