I have an old home-built one gallon rotary drum tumbler that I filled with walnut shell with red rouge for reloading brass. I have recently aquirred two vibratory untis. The five gallon model will be used for de-burring machine work and cleanup/smoothing of corroded metals, using the usual abrasive impregnated plastic rods and triangles in water, leaving a matte finish. The smaller 1.5 gallon unit will be used for reloading brass as well as shining up bead-blasted aluminum and brass antique items. Walnut with rouge has served me well, but have read of others using rice for a no-dust finish, or just plain walnut shell reptile bedding without abrasives added. . What are your current favorites?