We got the 2 gallon version due to having two large-ish dogs (about 70 and 50lbs). Minus one star for noise level produced by the "water fountain." Minus a second star for the way the filters are sold. We only used this a couple weeks so far, so no long term use feedback. Possibly the loudness is difficult to avoid when pushing this much water, but if amazon reviewers can find fixes, you'd think the manufacturer could too. It is not an obnoxious sound for us, but we found it to be pretty loud, especially at sleeping times when the house was silent. We had this on tile in our kitchen in a ~1800sq/ft house. In addition and specific to our scenario: 1. Our dogs have never been fond of plastic water containers. This is 99% plastic, if not more. The dogs would drink from it since it was the only water source, but I'm not sure they increased how much they were drinking, as intended with the fountain. Also, as soon as it got a little dirty, they stopped drinking - I think the combo of the plastic and poor water quality made them stop drinking at a week and a half of use, because it was only a little dirty. It is somewhere in the instructions, but it does say in the manual, and probably here on amazon, that if multiple pets are using the fountain, it should be cleaned more often, so once a month cleaning becomes at least twice a month. 2. Cleaning it would not be so bad, but it is giant and cumbersome and awkward to work with. If you have a open style double sink (farmhouse style for ex) or use a bath tub, maybe you wouldn't mind so much. Also, the white water spots develop quickly in the areas that are not submersed. 3. Our dogs would splash a little outside the fountain, so almost constantly a little puddle a few inches in diameter in front of it. They also had to get used to it (noise and fountain type water source versus bowl), so a typical adjustment period as well. 4. The filters. The filters are recommended to replace the carbon one every two weeks or so and the sponge once a month (?) or so. The sponge can only be found in a package with one sponge and multiple carbons forcing you to stay on the manufacturer's schedule or buy more product that you might not need. Upon going to clean ours at something just shy of 2 weeks, the white sponge was off white, implying dirty, and the carbon just looked hairy. Possibly we could just rinse all these out really well and go on with life, but its not ideal. Of course, you could get some materials, from the maybe the fish store or department, and try to make the sponge yourself, but you should be able to buy the filters separately to suit your needs. We want our dogs to drink more water, but were not expecting to be constantly cleaning this huge machine and replacing/creating filters, so we will look at other options. These issues are why we no longer have a fish tank, for example, and again, specific to us and the level of bother that we want to deal with. I did do research before the purchase and did not see a better option, but will now be double checking.
