We make it so: in our thermos flask, the water cools by approximately 1 ° per hour. If is therefore foreseeable that we need in 3 hours 37 ° warm water (our baby drinks relatively regularly), we take 40 ° / 41 ° warm water and the amount required and a Vial Pulverportionierer finished. If necessary we can then shake everything together and usually no waiting time immediately verfüttern- the less than a minute. Since vessel accounted for warming and scissors, we have less here (and the less you have to take / the less you can forget at home the better !!), it's faster and it's much cheaper too.
In my opinion, these ready-to-milk brings no added value, but on the contrary still more complicated. The finished milk ends up for me in the drawer "things that no one needs a closer look."