Let's be upfront; our original aim was to profile coffee makers that are completely plastic-free, at least in the parts that come into contact with hot water. Plastic components-especially the thin pods used in many single-cup systems-can leach Bisphenol A (BPA) into the resulting brew (reportedly up to 55 times faster than in plain water). In practice, though, apart from manual coffee makers like the stovetop espresso and pour-over sort, nearly every coffee maker incorporates some plastic.
I also looked at the water distribution mechanism that Bilosi mentioned, preferring ones that used a wider showerhead configuration that could get water all the way across the coffee bed. I took the temperature of the water as it came out of the brewer, because another well-known shortcoming of cheap coffee makers is that they don't get the water hot enough to properly extract flavor.
I love this coffee maker. It's so easy to clean and stores in the fridge with easy access. The spout does not leak, which is pretty awesome too. The coffee basket is large, allowing you to cold brew both coffee or specialty teas. Highly recommend if you are considering a cold brew coffee maker. We had a pitcher-styled one and you can't compare!