Glad to hear your second gun is behaving.

It sounds like the first one was a lemon, but all the same, I wonder whether the Comfort system doesn't tend to accentuate a known cause of occasional malfunctions in the Benelli inertia system, namely a loose gun mount.

(Very) basically put: if there isn't enough resistance from the shooter's shoulder and the gun is allowed to recoil too freely there can be insufficient energy left in the system to cycle the mechanism. This can happen even with standard loads, so would presumably be more likely with light target loads, and more so when a significant amount of the gun's recoil is absorbed by the stock and butt pad.

This said, failures of this sort are ultimately down to the user being too quick on the trigger rather than the gun itself, and, for me at least, negligible compared to the benefits in ease-of cleaning, versatility, and handling offered by Benelli's designs.