I have the Keurig 2.0 system and one thing I have learned from owning it is that you have to do the maintenance on it so you always have great coffee when you brew a cup. I already use filtered water from my Clearly filtered pitcher but this Keurig also has a charcoal filter in the Water container, which needs periodic changing. I have the brewer remind me to change it after the programed amount of brews. It is easy to do along as you pre-soak the filter inside the filter holder because it gets bigger as it pre-soaks and you can't fit it inside. All of this is shown in the helpful videos on the site. I was buying the smaller pack of two but buying the 6 pack better economically.