You definitely adjust to driving a fast car and begin to think of it as normal. My 118TSI is slower than my previous car, and it still feels to me like I have to rev it pretty high if I want it moving in a hurry. But every time I drive another (more 'normal') car, I'm reminded that compared to most of what's on the road, even the Golf TSI is pretty quick.
mfl's comment about turbo'd cars being slower in hot weather might also be relevant. This was really noticeable in my old Ford XR5 which was very much designed for European conditions: both the engine and the air conditioner were happier when it was below 30 degrees outside. Lots of people on the XR5 forums had fitted larger intercoolers to help make up for that. I'm assuming that the Golf GTI isn't quite so bad because I haven't seen anyone here mentioning doing that - and I'm sure that if it was a problem, a company like APR would step up to provide an aftermarket solution.
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