Normally, I would have just bought the exact same model, or a model that I knew (to some degree of certainty) was better than what I already had… but since I was trying to save a few bucks and was going used, I was the whim of what was available. I found the K40 listed on Craigslist for only $65, and the seller was including about 75 k-cups. This is without a doubt a great deal, so I jumped on it. The machines themselves run about $100 new, and k-cups can get rather pricey, ranging from $0.40/k-cup to $0.60/k-cup.

I want to focus on the differences between these two machines, as they really do have some big ones. I’ll start by saying I am less happy with the K40 machine. It only has two size options (unlike what a lot of other websites claim). In comparison, the K45 actually has three size options. Furthermore, it feels like the K40’s largest size option is rather small. I put a standard coffee mug in the machine, pressed the largest size option, and end up with about half a mug full of coffee. I haven’t done an oz-for-oz comparison yet, and I’ll admit the mug I use at work is not the same kind of mug, so I’m far from making a quantitative measurement here (maybe I’ll do that soon and update this) but it definitely feels like the K40 is not producing as much as I want it to.

The second difference is that the K40 seems to take longer to heat the water. I’m not sure if this could be because it’s “used” (who knows what kind of stress the last guy put on it) or if it’s because I keep my house a little colder than the office (the difference would only be a few degrees at most). Whatever the reason, it feels like the K40 takes about twice as long to heat up as the K45.

So that’s about it, just those two issues. They are otherwise comparable machines, but honestly, I wish I had two of the K45’s instead. Oh well, for the discount I got, it was well worth it!