A.Rex Cauldwell responds: When 1.6-gallon toilets first came out, they did not work well because they were not designed for low flush: They were essentially 3.5-gallon toilets with a 1.6-gallon tank capacity. Everyone had trouble with them (you had to flush twice), so many consumers resorted to pressure-assisted units. Pressure-assisted units typically work well in the beginning (although many are noisy), but may eventually need repairs. In some cases parts may be hard to find.
I prefer to keep it simple and use a gravity toilet. Most of the new 1.6-gallon designs work fine. However, when replacing a 3.5-gallon unit with a low-flow, I try to keep the customer’s expectations in line. Skid marks are a problem with all the units and are just something they’ll have to live with. Some manufacturers give a written one-flush...
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