While all of the above is true regarding beans, water, and burr set, do not overlook how the burr set is implemented. Some cheaper grinders use a good burr set, but the adjustment mechanism or bearings are wonky. This results in the same inconsistent grind as a lesser quality burr set. I have seen some articles recommending using tape to keep the burr set stable. For home use, I use the original OE Lido. For travel, I use the Zassenhaus Panama.