Let's get the bad stuff out of the way first. This grinder is slow. S. L. O. W. I've harped on the motor issues enough (well, at least until the next page) but as this test period with the Innova grinders progressed, I was thinking more and more that a complete motor change in this grinder would solve many of my gripes. At the very least, a motor chance should greatly reduce the impact of many of the problems I've outlined in this detailed review.
A balance needs to be found between grinding too slow or burning the beans. I know this is a serious concern for any grinder maker, and I feel that the Innovas fall too much on the "slow" side.
I also have concerns about the longevity of this product. I have no real way of simulating several years' worth of use with this grinder unless I'm prepared to attach a 100lb bag of roasted beans to it, and build a special device that would not only turn the grinder on and off for 30 seconds at a shot, but also empty out the doser as it went along.
Since I can't do that, all I can do is ask people who know better than I about motor issues and longevity. The basic consensus amongst those I asked is that while the torque issues and poor gearing may not overly harm the grinder's motor, they certainly aren't helping it.
If the motor issues can eventually be resolved in the years ahead if Innova continues as a brand, I could actually see this grinder performing light commercial duties with aplomb, even with the amount of grinds left in the chute. But at roughly 30+ seconds to grind a double, it's actually slower than your espresso machine takes to brew the shot, and is definitely too slow for any kind of serious high volume use.
The Good Stuff, Performance-Wise
As far as the grind this grinder produces, well, compared to most grinders, this grinder rocks. (did we use the word grind enough?)
Rock. It really does. Judging solely on two things - grind quality and grind control, this grinder has few equals in its price range, or even above it. The grind quality is probably equal to the Rocky or Mazzer Mini to the average espresso enthusiast, but the combination of control, super fine tuning, and the process of "dialing yourself" into the grinder's ability push it a level above.
I was continually impressed with one specific aspect. With my Rossi RR45 grinder, the grinder I used day in and day out before the Innovas were dropped on my doorstep, I'd often go through several shots each morning finding the right "mix" that produced a great espresso shot. This was after many, many months getting to know the Rossi. I even upgraded the selector dial on it to the 80 clicks model (it had a 40 click selector on it when I bought it), just to aid me in getting it "right" each morning. It did help, but not a lot - on some days, I just couldn't get in tune with that Rossi.
By contrast, after using the Innovas heavily for a week or two, I was getting to the point where in the mornings, if my first shot was off a bit, I knew that one or two revolutions on the grind selector, tied in with the exact same tamp I used on the previous shot would combine to deliver me the goods. And it almost always did. One thing I notice about my own espresso barista skills is this - I sometimes overcompensate when trying to adjust my variables. The Innova helps prevent this - and that, more than almost any other positive feature of this grinder, was the biggest selling point for me.
The contrast between the conical burr model and flat burr model did show up in performance usage, but also with an anomaly. I found the more powerful motor in the flat burr model handled torque a lot better and had a very even grind performance. The conical burr had noticeable speed changes while under load, but in extensive taste testing by myself and my various espresso buddy guinea pigs, almost all of us gave a very slight nod to the conical model for consistently producing better shots. I have no explanation for this, other than maybe the larger cutting surface of the conical burrs (which, in theory should create longer but thinner strands of grinds) may have led to slightly more extraction capabilities from the coffee.
I have to be very clear here though - it was so close that it took some serious double and triple taste testing to even notice it. And our approach was very unscientific. We had both grinders lined up. I dialed in each one individually with test shots. Then I would pull consecutive shots on a Livia 90 from both grinders, using the same batch of beans, and doling out the cups.