I just bought a Beretta A400 with the Kick-Off system. I wrote an informal report here
. I used it at the skeet and trap range, as well as on 3 duck hunts. The cleaning is a bit complicated the first time around, but as mentioned, Beretta has a great video on their website.
I can't comment on the Benelli, but hopefully other members can chime.
For me, the reliability was perfect and recoil was very managable with full power 3" loads. I felt the gun was pretty light, but a side by side comparison confirmed that the Beretta Urica was lighter, even with wood stocks.