I am really all talked out on this subject. But here is some quick information:
1. We don't use the "bottom of the line" of their regulators. We actually have mid-range diaphragm first stages, 2 or 3 different models. The models we have are 2 -3 years old and perhaps not current models.
2. Parts not cheap since we will have to order them from Italy or send the regulators overseas for repairs (which we just did and it is a nightmare).
3. The second stage housings are horrible. They don't stand up to use (and we are careful in handling our equipment as much as possible). The ss body get scratched very badly and the front cover with purge button get damaged easily.
4. They need constant adjustment and tend to have severe free flow issues frequently where we don't have anywhere nearly as much issues with other brands (we have some issues with Mares second stages that free flow but never with SP or Atomic or AL).
5. A local police marine rescue team unloaded (sold VERY cheaply) all of their Cressi regulators because they didn't stand up to use and just had one problem after another. They replaced them with AL LX (I think) and no issue since they done that last year AFAIK.
6. They don't come on your bench as often as other brands is probably due to the fact that not too many people buy or keep them
7. Reliability testing is done by using them, it isn't difficult to do that, and we keep track of what has what problem and when and compare records. Cressi had the worst track record. This isn't just our dive school but also police rescue teams, private and commercial fishermen divers, etc. It is a very small community where we are and everyone knows and talks to everyone else.
8. BC's; they don't hold up or fit or as comfortable as other brands but not as bad as their regulators.
9. Fins, mask and other free diving equipment: I am talking strictly scuba equipment. Cressi appears to make decent free-diving and spearfishing equipment but I can't judge it since we don't deal with it at all.
I hope that the above is more clear but this is as much as I can/want to talk about the subject. I am not sure of how many other ways I can clarify it.
BTW, I have few MKII's I bought circa 2004 and use in our training program and we NEVER had any issues with them at all, I mean AT ALL. Our students and staff learned to always reach for the SP and Atomic regulators first and those that are late may have only Cressi and not like it.