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The most versatile O/U in the Browning Citori lineup, in my opinion - is the Citori XS Skeet model with the adjustable comb. Here is a link to the model..
http://www.browning.com/products/catalog/firearms/detail.asp?value=008B&cat_id=013&type_id=066
The gun has very good balance / nice wood on most of them - and is a gun that will easily last you 100,000 shells or more (I've frankly never worn one out ). If you purchase some extended chokes for it ( and I recommend 2 Skeet, 2 Improved Cyclinder, 2 Mod, 1 Improved Mod, 1 Full ) - and I like the Browning Midas Grade or the Diana grade ( so it's another $ 500 for the chokes you'll need ) and a nice Browning take down hard case for about $ 175 - I think you are all set and under your budget.
The XS Skeet is selling new for about $ 2,850 in my area. I like it with 30" barrels. It is my primary gun for Skeet, Sporting Clays and bird hunting. I do not use it for a dedicated Trap gun ( I go with the Browning XT with adj comb for Trap ) but at around 10 lbs its too heavy and clumsy for Skeet or hunting.
I think Browning gives you a lot of gun for the money. The parallel comb - with the adj comb in it / makes it a gun that can be adjusted to fit most anyone and that's the biggest plus of this model. Its my opinion, that guns with angled combs are a mistake for a general purpose gun / unless you know what stock dimensions exactly fit you - and you're prepared to pay for a truly custom stock on a custom gun ( like a Kolar, Krieghoff, Blaser or Perazzi ) and those are all way out of your budget range.
My XS Skeet models in 12ga, 20ga, 28ga and .410 - I shoot these guns all the time.
http://www.thefiringline.com/forums/attachment.php?attachmentid=43351&d=1236031020
Here are my primary Trap guns ( Browning XT models, 32" barrels, one with a GraCoil system and upgraded wood ) / one is stock - both with adj combs.
http://www.thefiringline.com/forums/attachment.php?attachmentid=47539&d=1243443556
The XS Skeet is also a gun that is very easy to sell / if you take care of it down the road / if you want something different. In my area used a good XS Skeet is selling for $ 2,600 easily these days in 12ga or 20ga / and there are some available in 28ga and .410 / they were special ordered by a number of dealers over the years ( the 28ga and .410 are built on the 20ga receiver in the XS Skeet ) and they're identical to the 20ga.
Take care.