all of those cars have high odds of being "ran hard and put away wet". Don't know what you plan on for mods (outside of the audio system), but that could be a factor.
I'll give you my biased opinion about the MKV GTI (as I have one); I think it's a blast. DSG is great, even after 10 years of driving a stick. It's not the fastest on the block, but a $600 chip will put 50hp and 70+ ft/lbs on it. It is pretty well sound insulated. I average 27 mpg on freeway trips at 75-80 mph.
I'd stay away from the MKIV GTIs as they've had serious reliability issues.
As for driving stick in heavy traffic - it's all about the 2nd gear crawl. You just creep along, leaving a considerable distance from the person in front of you, all while maintaining your cool 7 mph crawl. Use an example from truckers - you don't see them blasting up behind the car in front of them only to stand on their brakes every 5 seconds.