My previous car was an A3 1.8T Sport - 150bhp turbo-charged 1.8 litre petrol engine. When I came to change my car the first car I test drove was the 150bhp 2.0 FSI version as I thought that would be the nearest equivalent to the T Sport. It was hopeless, no go at low revs at all - horrible to drive on other that A roads or motorways.
The next car I drove was a manual 2.0TDI. This had a lot more go especially for overtaking and in country lanes etc but required much more gear-changing than than I was used to with 1.8T petrol engine and the actual gear change was no better. OK but not wonderfull.
The next car to be tested was a 2.0TDI but with the DSG gearbox. This had all the go of the 2.0TDI, still required a lot of gearchanging but the actual gear-changing using the 'manual' mode was so much more pleasant that having to keep using the manual clutch. A quick press on the central lever or click of the paddles. It brought a whole new level of sophistication to gear-changing without taking away any of the enjoyment of driving. Long journeys became so relaxed and short trips through the lanes even more fun. Power assisted gear-changing.
Personally I found that both TDI engines behaved in the same manner and required the same amount of gear-changing but the actual gear-changing experience was so much better using the DSG than the Manual. Hence I bought the DSG version and have been perfectly happy with my choice and have never regretted it.