re: Difference in the Keurig models?

mine has 4 or 5 different sizes, plus the water tank is a plus. the low end heats and brews each time you put a k cup in and doesn't have an on/off button.

I just turn mine on and it heats up once then you can brew as many cups as you want, provided you have water in the tank.

after owning both the low end and the high end, the high end obviously blows the other out of the water, but it is a bit pricier.