You really notice it when you get in a car that doesn't have it. I drove a friend of mine M3 that was bone stock, definitely felt a difference. My car felt like it was chomping at the bit, while his was on a Valium.
2013 M3 Coupe-MR/BLK ZCP, ACM test pipes, BPM Stg2 dev. tune and Megan catback, AFE Stg2. with C/F elbow
Previous rides: 2011 M3 Coupe-MR/Blk
2007 Porsche 997C2S Speed Yellow/Blk sport seats
2004 BMW M3 Imola/Blk