I just bought a tub of SWRA, and I am still working on a pouch, so I think I'll let the tub stay sealed for a year or two at least. As a generality, I think tub tobacco stores well. In this case, the burley and Virginia components remain good or improve a little. Likely the liqueurs fade somewhat, but they may also mellow. I'm expecting good things. It's not a match by a long shot, but a tub of PC Chestnut I've been nibbling at for two or three years, a blend of five or six tobaccos and a non-aromatic, has if anything improved a little with time, and it wasn't bad to start.