Difference between turbine regular and pearl

[hd800op]

The only reason I am asking is because the MSRP of these was different, now they can be found on amazon for about the same price. Also, why does the copper cost less than the gold if it is the "top end" earphone.

So my question:
Is there a difference in sound quality/tonal signature?
Which one do you think looks better
 


 
Looking for something that will complement my V-Moda M-100s