uhm okay, heres a question for you, whats the advantage of an EAI or even campy cog over a Shimano or whatever brand one?

I presume its machined better and probably out of harder metals? But if so, is it really worth what I presume is extra expenditure when the likelyhood of you putting enough kilometers on any cog to wear it to nubs is slim to none? Is it just for the kudos of having a sweet cog under all the road grime?

I dont fully understand cog vs. cog discussion, can anyone explain?


EDIT: im aware i presumed shimano is cheaper than EAI and campy, if wrong, sorry.