I bought this about a month ago, it is a lovely bottle,the one this I find annoying is, and I think it is because of the filter, is that when drinking through the bottle, you don't get a constant flow. It is almost like the water is not getting through filter and does not flow through. Almost feels like your sucking on fresh air sometimes. I have tried removing the filer and adding this again, making cap tigher doesn't impact on this.