Will not grind finer than a commercial 'espresso' grind
Could use more grind steps
The Pro-line was bought as a replacement for a Starbucks Barista grinder and is used with a Krups Novo Compact espresso machine. The comments below are in comparison with this equipment.
Build - The machine is built like a tank. The only visible plastic parts are the hopper lid, grind dial, and the grind control gear under the dial. The housing is die-cast metal, the interior parts are heavy machined metal and the two hoppers are glass. The bean hopper screws in and the coffee bin is held in by a friction fitting. The switch is a heavy duty toggle. I consider this heavy duty construction a great advantage because cheap plastic parts broke in my Barista grinder .
The machine is an aesthetic descendent to the Norman Bel Geddes school of streamlined deco design, much like the rest of Kitchenaid product line. For my wife, this was much preferrable to the minimalist, modernist design of Italian grinders.
Operation - The grinder is straightforward to use. The throat of the hopper does have ledges that catches beans as detailed in previous reviews. The grind dial is calibrated from 1 to 8 with half positions for 15 total positions. The on/off toggle is on the side of the machine. For some, a timer is preferable to a toggle but for me that is one more fragile piece to break. The grinder is doserless and meant to be more than a espresso only grinder so the side position makes sense for this machine. The bottom coffee hopper takes a little practice to move in and out, but seals well. The shape of the hopper makes it fairly easy to pour coffee into a portafilter. The use of glass rather than plastic for the hopper eliminates the static cling of ground coffee.
The grinder from the factory is adjusted to be balanced between a coarse and fine grind. The grinder can be skewed toward finer grinds or coarser grinds by removing the grind dial with an Allen wrench and turning a grind control gear. Surprisingly, the gear only moved three clicks before the grinding burrs contacted. More adjustment would make this grinder more versatile.
Cleaning the grinder is fairly straightforward as well, although it takes a screwdriver to remove the faceplate to get to the burrs. The burr shaft piece is also difficult to pull out if you do not clean the grinder regularly.
Grind - Visually comparing the finest grind from this machine with a store ground espresso, the Pro-Line can grind to the same particle size as the commercially ground coffee. The coffee particles are not as consistent in size as the commercially ground, but are more consistent than with the Barista.
The major problem for a mostly espresso user is that the Pro-Line cannot grind any finer. While the grind works well with my Krups espresso machine, some users will want to go to almost a Turkish grind. An increase in the number of grind steps or adjustment would help this machine's acceptance by strictly espresso users.
Manual - The manual is clearly written and illustrated.
While the salespeople at William-Sonoma have no clue about the coffee equipment they sell, they work to be helpful.