Just thought I would let you know about a problem I've had, as I have seen the initial symptoms mentioned on these forums before.
My july 07 GTI with 72k miles on the clock has just killed it's flywheel. The effect was a very juddery idle with massive feedback coming through the pedal box and the car sounding like a tractor.
I mention it on the forum as I have previously had, on about 4 occasions, problems with the car sounding like a tractor when I started it. If I then turned the car off and restarted it, everything was fine.
Iirc in the posts it was just thought to be an intermittent problem and something to do with the crankcase needing to be pressurised in the TSI engine.
I could be wrong and the two events may not be related in any way, it just occurs to me that the judder and the noise made by the car were the same in both cases.
My engine isn't modded in any way, so it should be okay. But I thought I would put this up as a warning if anyone is getting problems with the car on starting, it might be worth getting the garage to give it a looking over.