there a was of money, they only look diffrent thats it.
and there are better give less resistance giving a better spark
i brought some off those hose cover things for £10 a few years ago...put them on and ripped them off in under an hour look a mess imo lol.
yearh i have a set of magnecore's kv85's iirc (that i got given) theres no diffrance atall bar the fact there red and have magnecore wrote on them with numbers 1234 lol