The MACAP M4 Stepless Adjustment Espresso Grinder is a superb machine, which I would rate even higher were it more straight forward to setup. It's well built, attractive, easy to use, has a nice doser mechanism, and produces an excellent, uniform and highly aromatic grind.

Initial setup could be made easier. Instruction are less that they should be.

This is a wonderful grinder once set up. The only weak point that I have encountered so far is that initial setup can be a little frustrating. So here are some tips:
It's a professional espresso grinder, shipped with the assumption that you know exactly what to do with it without being told. The factory instructions are of no help. The supplemental English instructions get you half way there. They tell you how to find the "Zero Point," (which takes less than a minute), and then to move "21/2 numbers higher" and you should be in espresso territory. Well, definitely not in my case.  To make matters easier, you can place a dot with nail polish or a permanent marker on the top front of the grinder, and a similar mark on the toothed collar above the dot when you find the zero point. Now you have a permanent reference. On my grinder the zero point was at 5.6 on the scale. 21/2 higher was much too coarse for espresso. If your grinder is like mine, I would suggest starting at 11/2 numbers higher (i.e around 7.1) in order to minimize waste of precious coffee, while you fine tune. I like my espresso more on the ristretto side and am usually below 7 on mine, with my various home-roasted coffees.
The flavor of the coffee with this grinder is exceptional, using my Anita. Heck, just the aroma while grinding is pure joy. My previous grinder was a Solis Maestro, so I am not claiming expert status.
Doser or Doserless? At first I was unsure, but finally decided on the doser model, and am glad I did. I reasoned that with three coffee drinkers in the family, it would be easier to have the grinder grinding for three, while I tamped and made coffee. Also, it has a rest for the portafilter, which I use to rest and tap while filling. What about stale grinds collecting in the doser? Well, stale grinds will collect around the grinding burrs, in the exit shoot, and in the doser. If you are intent on having the freshest, most flavorful coffee, then you can buy an inexpensive vacuum micro attachment kit, such as the superb one sold by cyberguys & Amazon, which comes with adaptors for home or shop vacs. I keep mine attached to a small 1 gallon shop vac that hides behind my coffee counter. This makes removing old grinds at the end of the day quick and effortless, and would be much the same for either version.
To improve functionality to my taste, I left off the plastic tamper on the front (the better to see), removed the obstructing slide in the coffee tub (just push the tab with the tip of a chop stick and it slides right out), and removed the obstructing guard in the doser (2 screws). This also makes cleaning much easier. However if you live with uncommonly accident-prone individuals,  then, of course, don't do this.
All in all, a joy.

I purchased the grinder, along with  Anita,  from Chris Coffee Service, and was very impressed with the service. After a week, the brew lever on my Anita stopped staying all the way down (it still worked). When I called in, I was quickly transferred to a technician, who told me which spring to stretch and how to do it. It took no more than 2 or 3 minutes to carry out, and I was back in business. Highly recommended.