The mkvi gti has been a surprisingly reliable car so far.
I expected more electrical issues and other finicky VW things, but my 2010 (for the most part) has been rock solid. The carbon deposit issue on the back of the intake ports is definitely a problem, but this is not specific to the gti or VW, rather for all direct-injected motors. That is definitely something to be aware of when purchasing a car that has a DI turbo motor.
My only regret is not getting the 4-dr model since I now have an infant, but other than that I have no regrets. This is a great car for someone looking for a quality interior, sporty feel, reasonable utility, and reasonable price. Great all-around car for the realistic enthusiast in need of a daily driver.