we just got the K600 in the mail for review. Why you made this to not use a paper filter as was able to be used in the original My K Cup reusable filter is quite evident to me. You do not want people to have the pleasure of drinking sediment free cofee, and since your stupid system of reflective ink could be over-ridden easilt you are now selling these, so that they are eventlly throw away. Can't force people to buy your brand, so they  will pay you some other way.
The coffee tastes much better filtered. Stop being so greedy. Make the cup able to use filter paper as before. If not I will go back to perked.