I'm hesitant to use bussing tubs, they are thicker, sturdier and all around sound great, but those darn edges at the bottom! I've had big rats chew the small mounded dimples on the bottom of the mortar tubs, I just couldn't risk anyone getting a tooth around the bottom of the bussing tubs.

TSC had a litterpan I would use in a heartbeat, but I can't for the life of me remember what the name was, or even if they carry them anymore.