I had an S3 with about £4.5k of modifications on it; remap to 270bhp, coilovers, stiffened anti-roll bars, uprated brakes and lots of other little modifications. It was quicker than a Boxter and very agile indeed. I was trying to hang on for the new S, but there was no sign and my itchy feet couldn't wait any longer so I upgraded to a 3.2 S-Line Sportback with DSG.
In terms of feel, the S3 was way better than my 3.2. The explosive acceleration and the levels of grip were outstanding with the uprated S3. The 3.2 is much more refined and doesn't inspire to quite the same level of confidence, though I would say it was as good as an unmodified S3.
On the other hand, the 3.2 is a very relaxing car to drive when you want it to be. I am a total convert to DSG; it makes driving in traffic effortless, and once you understand how it works you can use it to drive just as sportingly as a manual. The engine noise on the motorway is less too.
I went on the Audi driving day just before Easter, and learned a lot about the abilities of the Audi's involved, and how to drive them better. Since that I have driven the car much more effectively, and I would heartily recommend the day to anyone.
Dan