My 12ga Beretta 390 will cycle my 3/4oz 1200fps and 7/8oz 1100fps loads with one hundred percent reliability, just as it does with heavy loads. It's the first semi that I've ever owned that truly has been flawless with every possible load that I've tried.
I own 2 390's and this has been exactly my experience. I had one hang fire on one of my 390 in many thousands of rounds. I remember when it happened, I pulled the trigger, got a click, and thought, well I guess I finally got my first failure. Then as I began to lower the gun from my shoulder...BANG! Only time either gun has had any issue of any kind and it turned out to be an ammo issue. FYI, I traded in an 11-87 for one of the 390's because of persistent failure to feed issues.