I agree with KayBea. Whilst on the surface they are quite useful, they are quite faffy. You have to remember to charge the warmer well in advance of when you want to use it, and I also find that it takes longer than the advertised 60 seconds to heat up the milk to the required temp. It's then also a real faff to unscrew the teat and remove the warmer from inside the bottle before you can feed LO (unless I've been doing it wrong!). Although it has been useful on occasion, I now barely use it and at around £25 for one bottle and a warmer, I don't think it's worth the price. All IMO of course!