I have been using this maker for 30 days. After the 3rd day it would only brew one cup of coffee and then shut itself off due to a malfunction which is the unit cannot pump water from the clear reservoir. After it is shut off for say 30 minutes and is turned back on it will resume pumping and work correctly.
I contacted Keirig and they sent a replacement. The replacement would not ever pump water and would self shutdown after 45 seconds or so. I never was able to use it. Still using the original like stated above.
I have read a lot of reviews about this same problem and was hoping Keirig has the problem fixed as I really like the concept.
Also, Amazon stopped selling this model for about a week because of issues and I was wondering if the new stock actually works like it is supposed to.
Edited 03/31/10: I am still using the same unit, but with different results. For the last 3 weeks it has worked flawlessly (about 20 cups per week). For my unit anyway, it seems to have gotten better, much better over time. I'm sure it was not designed this way and I am still waiting to hear from people that have received a revised model. If you include your serial number it would be helpful. This is found behind the drip tray.
Edit 05/06/10: Still working flawlessly since early March. Strange I know.
Edit 06/15/10: Still working, no problems.
Edit 08/20/10: Still pumping without fail, however I have had a couple slow brews and partial cups, but rarely. May need to de-scale.
Edit 03/07/11: Still working. Only time I have had an additional problem was laying the unit on its side while we drove 12 hours. Got the air out and no problems since Oct 2010 with the exception of the occasional partial cup.
Edit 01/28/12: Been 2 years now. Same machine. 2 things I do and or don't do. 1. Use filtered water. 2. Never remove reservoir. Have descaled once in 2 years and even then it was very clean.