A:AnswerYes! At least for the 32 oz. I don't have a 44 oz. to check. But the bottom of the Keurig coffee thing comes off, so you can put large cups under it.
A:AnswerContact Keurig directly. If your machine is out of Best Buy' s warranty, odds are they'll take care of you. Every experience I or a family member has had with them has been great.
A:AnswerYeah, I have one and the tray comes out and it fits just right. I believe the refillable kcups works, I just ordered mine and waiting to use them.
A:AnswerLook at the metal plate on the bottom of the unit. Many of the K50 models are actually K40 models, but I don't think it really makes any difference, because they both have identical appearance and features.