Waimea, The SKB's and Brownings are really nice guns but expensive. It costs almost as much to convert an SKB trigger from inertia to mechanical as a Stoeger costs! I'm told that the conversion is about $300, while I paid $325 for my single trigger Stoeger (used of course).
I have been using a Stoeger Supreme, single trigger for about 4 years now and after some initial modifications for function, I've had no problems with it. I have found that with some people the gun will double but it never has with me. I tried to analyze what caused the doubling and came to the conclusion that the problem was with the trigger squeeze.
Some folks squeeze a shotgun trigger just like they would squeeze a target rifle trigger, pressing back slowly until the trigger breaks unexpectedly. When the gun recoils from the first shot, the finger is separated from the trigger for a split second, but during recovery the finger re-engages the trigger and pulls it a second time. The result is a double shot.
I think that this could be remedied with heavier trigger springs and/or changing the angle on the sear engagement for a little heavier pull.
You are welcome to try out my Stoeger any time you'd like. Let me know. I'll have it at our match in Orlando on May 7.