Blade Grinders are the least expensive, but they are lacking in consistency and, the amount of friction has been known to burn the beans.
These would be a good alternative to buying previously ground coffee but are not for the coffee "aficionado".
The only positive of this type of grinder would be the ease of maintenance and care.
Flat Wheel Burr Grinders are priced in the middle of the three types and, as such, are the preferred method.
Their discs spin slower than a blade grinder creating lower points of friction and a much more consistent grind.
They are more expensive than the blade grinder and their consistency is sometimes in question but they will deliver a much more consistent product.
They need to be cleaned often and it is tough work...
but, worth it! Conical Burr Grinders are the Rolls-Royce of grinders because they spin even slower than the flat wheel burr grinder which allows them to give the most consistent grind while retaining the bulk of the flavor.
They are the most expensive and the most difficult to clean due to their slow spin speeds plus the increased friction which allows the ground coffee to adhere in the crevices.
As a result of there being three varieties of the fast touch coffee grinder..
the choices are wide and could be confusing.
The good news is that all major manufacturers of small appliances are in this market and they include names like Krups, Compak, Cuisinart, Hamilton Beach.
Capresso, Baratza, deLonghi, Black and Decker, Braun and more.