I did the besian seals. I noticed the difference right away. Although I did he vanos seals a little after I already had the supercharged in. But it was only running 6psi at that time and not it's current 8psi.
2006 BMW M5 - REALLY LOUD
2000 BMW 3-series supercharged 400hp
2004 Maserati M128 GT SOLD
2006 BMW M3 - SOLD