I presently have a cheap pair of Sony mdr-xd100 headphones. My question is: Is it worth shelling out an extra $90 for the increase in audio quality, by upgrading to an mdr-v6, or should I keep my present headphones? Because if, for example, I will get essentially the same frequency response from...

If price is no barrier, based on sound quality alone which would you choose: the Sony mdr-v6 of the mdr-1r?     And I know this sounds silly but how much of a difference in sound quality between let's say a low-end headphone, the mdr-xd100 and these high-end headphones )mdr-v6 and mdr-1r)?