Bests & Worsts Reviews from Amazon

I received a B77 as a gift at the end of Nov 2009. 3 days later it would not push water out through the K-cup. Exchanged it at Costco, worked great until 2 days ago. 1 month of light usage and it's having problems filling from the reservoir. Going to exchange it for a third but I'm not confident that the next unit will be trouble free. My brother's same unit that's a year old (and works fine) had a very loud fill pump. Keurig changed the pump design in the B77 to a small dc motor driven impeller pump. Much much quieter when filling, but apparently cannot always overcome the check valve after the pump. I always use RO water, and the unit is only 1 month old so scale is not the issue. I refill the tank when it's still on the machine, so no air to get in there to screw up the pump's priming. Google B70 pump problems. Edit: I did not bother to exchange the 2nd unit as from what I've read here and on SingleServeCoffee's website, all the B70/B77 are plaqued with this problem. Even ones directly purchased or replaced by Keurig. Maker will for for a few days or weeks, then suffer the "not ready" and then shutdown problem as it is unable to pull water from the reservoir into the heater. I put a review in on Keurig's website itself but it looks like they censor what gets posted or not, hence the glowing reviews there.