I've got one and I love it. It really works as promised and I can recommend it very much. Itís built-in 15 grades step-tablet allows you to make perfect guesses what negative densities will result in which paper densities. You can see how these values change while switching from one gradation to another. So perfect mid-tone separation is at your fingertips while burn-in calculations are just one other button press away, if necessary. No more trial and error printing.
You can even replace the 15 grades step-tablet with your own (i.e. to match warmtone or otherwise toned prints). Precise and quick calibration procedures help you to set up anything. I even use this device for color printing. There is no doubt: this device was built by a Practitioner and not by a Theorist.
The only wish that remains for me is an easier way to calculate and handle Splitgrades. It is possible, but it is sometimes hard to tell which tone values become which after switching to the second or even a third grade. And the necessary time difference calculations have to be done by hand, which seems to be computer irony to me.