Hello ladies and gentlemen.
I've found this thread an eye-opener - I never realised that the DSG had this 'kickdown' feature activated, even in manual mode. Like some other posters, I too had the idea that the manual mode was indeed 'manual' in that you just selected the gear you wanted (with consideration that you 'cannot' go into 2nd gear at 140mph ahem) and it would just stick in that gear.
In terms of my own personal experience, sometime last year I was lucky enough to briefly test drive a DSG equipped Golf GTI Mk5. I thought this is a brilliant driving experience! (actually in retrospect perhaps that might have been because that car had the most powerful engine I had ever driven...

) I had driven an automatic before but the DSG I thought and still think is an amazing piece of equipment. When I first drove it I thought "This is EXACTLY like Gran Turismo on the PlayStation!" To think that changing gear with pressing one little button instead of stomping on a pedal and having to move my hand from the wheel and wiggle a stick around, just unreal.
After reading this thread, as I've mentioned I've learned this kickdown is on even in manual mode. Personally I think this would put me off, even if I could feel in the right pedal where kickdown would be activated, the natural instinct would be to floor it if I wanted to go fast. I'm guessing many of you have played Gran Turismo. I play it with 'manual' gears shifting down and up with L2 + R2 buttons, and it would pee me off no end if the car started to change gears by itself. I'm guessing it would be something I would be able to adapt to if I did go for a DSG car, but still nontheless it seems to be a bit of a learning curve, and it means if somebody else were to drive the car, they would have to 'learn' too.
Plus another thing that I believe has not mentioned so far, is if you were wanting to do mad close-quarters Russ Swift style manoeuvres such as doughnuts, J-turns and whatever else you call these things, I understand you would need the direct control of a manual to achieve this. I've never been mad (or rich) enough to try this on my own car, but this is the kinda stuff I mean -
http://www.youtube.com/watch?v=SjDJwEfhmJoI've also been lucky enough to test drive a manual Mk6, and I echo what has been said before that if feels like a rifle bolt. Well, actually I can only imagine what that would feel like as I've never fired a gun, but the stick did feel firm but smooth when it shifted in, and the clutch pedal felt surprisingly light. Considering the level of power a GTI has, I think it's a very usable car for mere mortals like myself with arms only ever used to moving a USB mouse all day long...
For me, considering the stage where I am in my life (i.e. still young(ish) and no arthritis in the legs, and increased cost of DSG) I would choose a manual. Also picking manual will mean that if at some point I ever get fed up of a GTI, I could just get another car and not forget how to drive a manual and have to 'learn' to change gears again.
As for the slightly off-topic thing about 'shopping cars', well everybody has their own opinion of that. My own opinion is that the GTI is simply a very nice car. One of the things that stand out for me with the GTI is simply the versatility of it. Like lots of things in life I like things that are versatile. As a car, the GTI ticks lots and lots of boxes. It looks great, it drives great. I could drive to work in it, I could give my mates a lift in it, in 5 door guise my grandparents shouldn't have too much trouble getting in (although it's likely I should probably at least seen to be driving sensibly as a) I don't wanna kill my grandma b) don't want their teeth to fall out), it's got bootspace for luggage on the airport run. If I pulled up outside the house of a girl I was dating, there is half a chance she won't look at me funny and tell me to p155 0FF. And another point, if equipped with DSG, I can pretend I'm Lewis Hamilton and change gears with buttons on the steering wheel.
So, erm there is my 2 and a half pence on manual vs DSG. DSG is a great system, but manual will do fine.
Thank you for reading.