We use one of these for our outside cats.

Pros: works well

Cons: none

We have several of these at the shelter. They work very well as we don't have to worry about the cats running out of water. They are easy to clean and the water stays fresh for a long time. At home I have one and I like it, but I have one cat that continually tips it over (apparently likes water) so I have to make sure it is full always so it is too heavy for her to tip.

Pros: Makes life easier

Cons: None

I like this A LOT!
One of my dogs on my route has it, actually 2 dogs live there. The both have fresh water always ...
the dispenser keeps from too much coming out, just enough.
Easy to fill when you do not fill the water container up the entire way.
I like this and think I may buy it for myself!

Pros: very good product ...

Cons: none

These waterers are very handy, especially for multiple pet households. Petmate has water bottles that range in size from 2 quarts to 5 gallons, depending on your need. Our dogs love their 2.75 gallon waterer. However, the 2 quart waterer was too small for our cats. They were able to knock off the water bottle and create a wet mess.

The advantage of the water is being able to go longer without re-watering. I found that bits or food or treats ends up in the water hopper. Many times I need to clean the waterer before the bottle is empty.

Recently, I damaged a water bottle and it was easy to purchase a replacement through Petmate.

Pros: Good variety of sizes

Cons: pet backwash

I have a different model of this waterer, but it is a Petmate product, and works great. I have 3 of my own cats and use this for them. They never go thirsty unless i forget to fillit, which doesn't happen too often. I also have another water bowl out, but they always go to the automatic waterer.

Pros: works well

Cons: none