I find the bubbler itself to work great. The glycerin chiller gets cold in the freezer FAST, and works pretty well given its small size. I attempt to release the choke and draw the smoke slowly so that it has a chance to have meaningful contact with the chiller. Easier said than done sometimes, but I still like this really easy to use mini-rig when it’s just me having around. Side note: I have the full size glycerin STAX chamber for my big-rig, and it is the absolute BOMB.