One thing I liked about the BabyK was that I could manage my own inventory - I have a very liberal ordering allowance, and it was my decision how much of of a supply buffer to keep for problems (wasting cartridges, supply delays, civil insurrection, etc.). The NxStage "send inventory" system makes it hard to do this, unless one plays games and undercounts inventory.On-line inventory submission is convenient, though I wish their system would send out an automatic email with the list of what is going to be delivered.