I've had a 1200 Sport for the last 2 years and love the engine. Mine is the old 2 valve lump. There were issues with the cams on the first of the 4 valve engines but yours should be good as a 2011 bike. Although date of manufacture is a better guide, mine was almost a year old when I registered it. It's worth asking your dealer though.
Modern Guzzis are pretty reliable and beautiful things to ride. The gearbox on mine is the sweetest I've ever had and the CARC shaft drive is perfect. I don't notice it's there, no clunks or snatching at all.
What size tank is on yours? The 2011 model should have a 31 litre tank, the previous model had only 18 litres. My Sport has a very useful 23 litre tank which gives me around 230-250 mile range.
There's lots of good info on Guzzitech.com
Guzzis in general have water ingress issues with the speedo sender. The first thing you should do is pack the rubber boot with silicon grease. I did and haven't had any issues.
One major pain with owning a Guzzi though is the spares availability. It takes at least 2 weeks to get anything that your dealer has not got in stock. You can forget August as well as the factory is closed for the whole month! A guy on 1200sport.com has had his 4v in the dealers for 8 weeks awaiting parts for the cam upgrade. He's ended up buying another bike for the summer!!
Don't let this put you off though as they're a great bikes to own. Lots of noise and smiles