Speaker Cable Wireworld vs Straightwire

Hi all,

Looking for some input on the difference in sound between the Wireworld models III, III+, 5 against the Straightwire Crescendo, Crescendo II.

Thanks to all in advance.

I love my Straightwire and their customer service but never heard of Wireworld. 
^One of the original Straightwire guys went onto Wireworld.
It was the cable designer who left Straightwire and started WireWorld.

If possible get this 6/7 or 8 series WW which are significant improvements over the earlier models