If you are looking for a good exhaust system and a tune for your car look at BSR Tuning http://en.bsr.se/
I have there exhaust and tune on my 2001 S60 2.4T, its louder then factory but not so loud it drives your friends out of town,keep in mind that I still have the factory downpipe. I know that ...

BSR Tuning for a S60 2.4T as follow: Stage 1: PPC tune for the ECU. 252hp 302ft lb Stage 2: Cat back exhaust system with the same tune as Stage 1. 257hp 309ft lb Stage 3: PPC tune update for the ECU with a 3 inch down pipe plus race cat. 264hp 320ft lb Stage 4: PPC tune update for the ECU with new ...