Personally, I think nappy bins are a waste esp the automatic ones that ask you to buy special bags etc... We have a nappy safe, (was given to us for our first son 4 years ago). We used it a lot with him and I liked it b/c it takes any plastic bag and it just flips over the nappy. My 2nd son is now 15 months and I think we used the nappy safe for just the first 6 months. NOw it's in storage. In general, we never put our sons' dirty nappies in the safe as they would always go into a nappy bag, then into the main garbage immediately so it would be dumped out end of day. After 6 months, we just had a plastic bag on the door and dumped them all end of day when our main garbage would go out.