Bibbla, it depends. I used to have a K&N induction kit with a standard cold air feed, it sounded great but the gap from where the cold feed ended to the filter was huge so most of the cold air probably got intercepted by hot air by the time it reached the filter! At high revs Id say am induction will give you a slightly better gain over a replacement panel filter. Im running a standard air box with a replacement panel filter at the moment and at low revs it definately picks up a little better, no induction roar though
. The best to go for are the Viper style kits as they are totally enclosed and have a good air feed from the front of the car, sound good too....approx £250. Have a play around and see which one suits you........