For the record, it is a little loud when my kitty runs on it but it's essentially a treadmill for them. Nothing is truly silent. Treadmills aren't quiet either. Heck, actual little hamster wheels aren't that quiet either so I'm not sure what everyone that is complaining about expected. On the plus side though, I bought this about a year ago and it has held up super well, my cat likes to sprint on it, go for a quick walk, she also uses the carpet as a secondary scratching post and the carpet has stayed in really good shape and I have not had to reapply it. I'm thinking I may need to get a larger wheel though, my cat has gotten a little bigger so when she sprints she nearly reaches the top! It would be great if the base could be made to be universal for all of the wheel sizes without having to buy and an entirely new wheel set but then what do we do with the old wheel.. Will definitely be upgrading to a bigger one soon!
Mike 
