The Benelli's are good guns. They have good quality and are pretty reliable. The inertia system is a clever design that is easy to maintain. They are not without their problems. They have failers just like any other semi auto operating system. Dirty actions or recoil spring, cold lube problems, too low of power shells to name a few. They do have their own unique problems as well. The "Benelli Click" that was already mentioned is caused by the bolt accidently coming out of battery. The fact that they are inertia operated AND have a rotary bolt is the reason. Straight overhead shots usally result in a failure to cycle the action. Because they are the most expensive semi's, they have the expectation of being perfect by many.
The gas operated guns like the Gold and SX2 may not be quite as easy to clean as the Benelli's, but they are not that far behind. Other gas guns like the Franchi 612 and Weatherby SAS are easier to clean than the Benelli's if you include their recoil springs.