Hi all I'm in the UK so looking for the parts in this country and experiences. Has anyone just changed the air filter to a decent one like k&n and noticed results in Power?

I'm also after advice on a decent induction kit for the car too, more for power but sound would be a bonus if it doesn't affect the power side of things. I won't be do I g this one just yet but in the near future I will be hoping to add it.

Thanks