Since I cannot buy 5 gallon pails of reducer from SPI, I get 5 liter cans of a cheap urethane reducer in the "store brand." It would suck to use for painting, but it's acceptable as a gun rinse. Thankfully, long ago I bought a used solvent recycler that we can run our waste through. It doesn't work quite right, but it does well enough. I mix 2 parts recycled solvent with 1 part cheap reducer to make a gallon of all-purpose wash solvent, and that's what we use. The fresh reducer makes up for losses that occur by evaporation, etc. I think we are pretty lucky to have found a solvent recycler for cheap that continues to serve our needs. I'd encourage shops with even small volume to look into it as an investment, because it's a great way to minimize waste and drastically reduce costs on gun cleaning.