I have the stepped M5 and I can only agree with what you say regarding the quality of the unit. When mine turned up (purchased from Attilio !) i was also impressed with the quality of the packaging.
The Macap grinder itself just drips quality and after comparing thr M5 with a Mini Mazzer the M5 just seemed a better unit.
Mine is now 4-5 months old, and still impresses and with the quality and bullet proof feeling I am sure it will be sitting on my kitchen counter for many years to come.
BTW, I have seen the M5s big brother in use in commercial environments, which is a pretty good advertisement of the longetivity and reliability of these units.