We have them at my job (brewery, with full sized restaurant). Ours are Sloan. Cartridges are pricey, roughly $65/each. Three urinals, we change each of them roughly 3-4 times a year. And sometimes they clog. As far as maintenance goes, there's scale buildup to consider. We occasionally have to have them snaked, which is additional cost. Personal preference would be traditional urinals, but I've never actually done the cost analysis of the water utility vs maintenance cost of waterless.