The 09 had a couple of issues one being the rear sway bar was far to close to the tire. which ment you had to run aftermarket wheels to run larger tires. for 2010 they completly changed the rear sway bar so you no longer have to run aftermarket wheels.
The other issue the 09's had was they like to foul the plugs if you start and stop the engine quickly. They seem to run far to rich on inital start up and it takes a minute to burn it off. To fix this there was a programing change that seems to have fixed this.