HI, I will post my opinion if I may..
From my experience with home audio also car audio for the past 16 years and now 3 years with PC speakers (especially the Klipsch) I know this:
The longer the wire, the thicker it needs to be, (for example) if you are running the Klipsch PMU 5.1's with the stock wire I say is good for maybe 10 feet, for longer distance add the next thickness (like 14 gauge) for maybe 20 feet in length, adding thicker wire helps amps run cooler, and might sound a bit better I say maybe 5% better on the PMU 5.1, the benefit of thick wire is mostly heard with high power audio systems, like car audio or home audio running at 100w or more of power per channel, On my personal setup with my PMU's I use 12 gauge for the front and 14g for the rear and can barely tell the difference in sound from stock wire, but on my home theater setup I use all 12 gauge running on 5 speakers at 120watts RMS per speaker and can really tell the difference there. That fancy Mnster wire sux, is too pricey and cheap quality (now days) it was great back in the 90's but not anymore..Also when purchasing wire (any type) don't be fooled,, look for thickness in copper not thickness in the rubber around it and since copper is expensive, some wire making companies claim is thick wire when the truth is just thick insulating material and copper content is very low.
Hope this helps
Cheers,
Elliott[]