I've got the Green induction kit - wasn't too keen on it at first as it isn't a particularly good fit in the engine bay - but the sound is AWESOME! Apparently the Green is slightly louder than the K&N, but I haven't compared the two myself. I really like the look of it as well, definately better looking than the K&N IMO:


I made up a set of detailed instructions on how to fit the Green, which is in the 'How to...' section if you need any help