08 has a few upgrades, but engine power wise is very minimum, you are basically getting the same amount of power. But the drive train has been improved and the suspension system is a little better.
The thing is leasing it and buying it it's not the same thing. You can't do a single mod to your car, you can't go over the limit that are on the contract, you will be paying a lot more than buying in the long run.
If you don't plan on staying here a very long time, leasing it and just have fun driving its what you should do. But if you do like to stay, make sure you really love that car, and then buy it.