Decent but expensive replacement filters,
This review is from: BRITA Fill&Go Water Filter Bottle including 4 Filter Discs - Green (Kitchen & Home)
Customer review from the Amazon Vine Programme (What's this?)
The bottle is made of sturdy plastic which will take few knocks, and the top screws easily and had a drip-free seal. Inserting the filter is easy, but you must remember to run it/soak it in water for 30 seconds or so before inserting as this will wash away any residue and unpleasant taste (this is included in the instructions). You do need to suck the water (whether using a straw or not) which minimises and spillages if the bottle is knocked-over.
You are advised the change the filter every week, but it would have been more helpful to say replace after using it for so may litres of water, as daily consumption of water will vary considerably. At the time of writing the filters cost around £1 each which seems a bit steep if you're being advised to change them every week.