I noticed a pleasant change when i fitted the k&n panel, i agree with wot Rich ecks and Joz say here, its not gonna give lots of bbhp or anything but it does make for less annoyin flat spots and slightly greater throttle response. From my experience so far it was a good choice, tho i do have an apexi under my bed to give a nicer note someday. As for insurance, i personally wouldnt bother to declare a panl filter, thats bein WAY WAY to pernickity for me mate, its notloike u'v superglued a turbo onto it or anythin, its just a panel filter. Others of course may disagree, i know some folk do declare them, its really your own personal choice dude. Phil.