The Keurig B31 is largely identical to the earlier B30 — only with a few slight upgrades. Let's start with looking at the key features.
Features (bold represent changes from the B30)
The Keurig B31 differs very little from its predecessor, the B30. Like the B30, the B31 does not have a water reservoir. This means that you will need to add a cup of water each time you wish to brew your favorite k cup coffee, tea, or hot chocolate. While this is a bit of a hassle, it also means that you won't need to lug around and find space for a bulky water tank. We think this machine is ideal for dorm rooms and RVs, as well as for that quick weekend trip to the beach.
One of the natural questions we had was, "Does the B31 make any significant upgrades to the older B30?" In the end, the answer for us was, "not really."
While the option to have three different brewing sizes (the B30 only advertises one setting, 8oz) might seem like a significant improvement, it really isn't. You can easily brew a 6oz cup on the older model as well: you just add 6oz of water instead of 8oz at the very beginning. As for the 10oz drop, that will depend on your personal tastes. We find that coffees brewed with more than 9oz are quite weak since more water is being put through the same amount of coffee grounds. If you prefer a lighter coffee, then the 10oz setting might be a nice addition. Otherwise, you'll probably never use the largest setting.
There is a second upgrade on the B31 that is much better. The older model took a 3 full minutes to brew a cup of coffee. The B31 heats the water much more quickly, reducing the total brewing time to two minutes. We don't think you should upgrade from a B30 to a B31 just for this, but if you're trying to decide between the two, this feature certainly is convenient.
This is a fantastic brewer, and we've heard of very few problems. The only consistent complaint we get on the Keurig line of coffee makers is the water pump. Since the B31 doesn't have a water pump, very few people should experience any mechanical difficulties with their B31.
Keurig's customer service is absolutely top notch. If anything goes wrong with your machine during the one year warranty, Keurig is a breeze to work with.
The Keurig B31 Mini Plus is a great machine for those who are looking for coffee on the road or for those who don't have the space for one of the large models. The unit retails for $99.95, making it relatively inexpensive as far as k cup brewers go. The B31 is a welcome addition to Keurig's line of one cup coffee makers. If you're looking for a space-saving coffee maker, check out the Keurig B31 at Amazon.