Speaker cables can make a difference, both good and bad, and cost doesn't have a great deal to do with the result (IMHO). I think many folks use cable as a form of tone control to correct deficiencies in their basic electronics/speaker match, not to allow the signal from the amp to pass thru to the speaker with a minimum of change. Personally I would focus is on getting short runs of cable with the matching impedence/capacitance to your speakers. A cheap experiment - buy a couple of short runs of 8 - 10 guage twisted copper wire (50 cents a foot) and use them as a reference to how other cables sound in comparison, then decide if you are willing to pay for the difference. A caveat with cables - don't do short listening comparisons, let them play, or just rest, in the system for about 24 hours before you sit down to listen to them. You might be surprised - some cables that seem to shine in side by side comparisons can be down right irritating in long term listening.
Be careful, its a jungle out there!
Be careful, its a jungle out there!