Buying by brand name is not a good idea. Most brands make good models and poor models. Many of the water savers are very good, some are very bad. I was looking at a few the other day. Limiting it to standard looking models (no color or special designer looks) I found models priced from $39.95 to $289.95.
All the cheaper models (which likely make up 90+% of the total sold, especially to contractor homes) have 1.75" traps unglazed. The better ones had 2" or larger traps with additional water surface areas and the trap areas were glazed. Some even had special pressurized water tanks.
Consider the difference. Have you felt the surface of an unglazed ceramic surface? That along with poor design, small opening etc. all contribute to poor performance. Using a lot of water was just a cheap way of getting around bad design.
Get a good water saver and you will be fine. Get a cheap model of any design and you will have problems.
BTW most water savers have a dual flush system. A single press uses
1.6, holding it down gets you about twice that, which is about what the old ones used. So if you just hold the handle down a few seconds when needed, you get the additional flush as well as saving water when you don't need it.
A very large market for them are builders who want the cheapest thing that meets the code, so they all make one. You don't want this. They all also make nice looking models that have a lot of appeal until you get them home and you find that the working parts are the same as the builder's specials.
Consumer Reports magazine did a report on them not long ago, you should be able to find a copy in the library. That may help.
Most people seem to be very happy with the American Standard Cadet models. Note that they do make more than one model in that line and pay attention to the trap design in which one you pick. Others like the Gerber (sp) power flush line. They are a little nosier and have a little more complex flushing system, but it is very effective.
Lowes has a nice web page that shows photos of much of this and even more information.
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