It's like copper capacitors for $75 and polypropylene for $.75 for the same mfd's some people claim they can hear the difference, The build quality of the copper caps will be top notch, and the poly's ok.
Personally with my speakers, and at my age, hearing, I wouldn't be able to tell the difference.
Part of the price is the quality of the parts, then fit and finish, the rarity, the builder's name may have an influence,the perceived sound quality(not necessarily the specs) etc...