I have the LS-25 and its really good. Its neutral but also natural sounding. There is no artificial and unnatural sparkling highs that silver plating can give. There is a wide open and clear sound to these cables, with even balance. These speaker cables are not tone controls.
The only other cables by Colin I have had were the original TQ Black, but that was a long time ago in a very different system. But I feel these cables are much better than the TQ Black.
I would like to know how much better the LS-40 is over the LS-25. Not interested in the LS-50/80 which are just double runs of the LS-25/40