+1 for the 11-87
I'm a big fan of the 11-87. I've been using one since the mid-90s for 3-gun and clays. They do need to be kept cleaner than the Benelli, but on the plus side they are a lot cheaper (particulary used ones) and softer shooting. There is a huge array of accessories for them, and you can legally put a pistol-grip stock on them (which I find appealing, others may not). Mine has been 100% reliable provided I keep it clean, lubed and replace the consumable gas seal o-ring when I see signs of sluggish cycling. The Remington gas guns are as robust as hell - go to any clay club in the nation and you will find loaner Remington 1100s and 11-87s that have had tens of thousands of rounds through them without a major problem.
The Benellis, Winchester/FN and Beretta Extrema are other nice semi-autos, and I hear good things about the new Mossberg, but for my money I would go with a Remington gas gun every time.