In general, how does price relate to quality?

It does not.

Only knowing yourself and how you listen really helps here.

The most modern tools and materials may go in a direction that doesn't actually bring you joy.  What good is a pure diamond speaker cabinet if the end result is not what you want to listen to all night?

Reminds me of those solid gold monitors for $5 mil!

The higher the price the more "confirmation bias" comes into play!

Confirmation bias cuts both ways, people often think the cheap gear they bought are giant killers, which isn't true most of the time.