[quote user="silly"]For example I've heard the £400 Revolver RW16 sounding stunning on equipment way above their price level[/quote]
I never rate them that highly myself but if the revolver float you boat!
My neat are retail at around £5,000 and they would show £10,000 JBL the door, similarly at my last hifi party the puresound amp (£1,000) sounded better than Pink Triangle amp (£3,000) pic below...

So yes, the more expensive is does not mean better but Silly, you must agree that most High-end, when match correctly will totally out class the budget to midrange systems.
NOTE: I don't benefit from anything in this post. All my posts are based on my personal views and musical tastes.