reason for Mazzer absence is cost. won't buy used one.
judging from previous experience in other areas of not so pop interests, I'd say parts availability would be a problem for all. either price, promised delivery time or correct part would probably be a reason for disappointment so not really counting on that. We are a small not so mature market I guess
for that matter internet popularity, ebay presence or other well established e-shop support would be a plus.
anfim does seem to have a big footprint on the networked world. their local representative also seems genuinely enthusiastic about espresso, but don't know how big they are is terms of business to really count on that for years to come.anfim best seems a little 70's on the outside and has the smallest diameter burrs of the three. there is report for excellent dosing and no clamping as well.
cunill has 60mm burrs, appealing design especially the brasil, and the lower price. cons list the height for tauro, not so much internet presence and I think the bean hopper doesn't have an isolation door(sorry don't know what the term is)
compak k3 is the most expensive but is really nice aesthetically, solid 58 burrs, most popular on the web of the three and from what I know they are being represented by a big market player (for our market standards)