Do they matter and if so how much do they matter in the ratio of the cable itself ??
...
Speaking of the importance of connectors should include the option of their exclusion as well(at least as a principle reminder), insofar this is practical - something many seem to overlook, and not always for practical reasons.. I know stripping ones audio components of their power sockets(or connectors in general) to give room for hardwiring isn't what most would do, for several reasons(electrical safety regulations to be one of them, I gather), but think about it; when speaking of connectors their speculated/reported importance into sound influence often clouds the fact the they are simply mere assets of convenience and practicality - and, strictly speaking, are therefore unwanted - and so are less likely to be thought of in terms of their negation. Gadget-obsession perhaps, to put it differently. It's not that I question some importance of and sonic difference between connectors, which I understand your inquiry into, but simply, where this would be possible and practical in your case, to invest the thought into excluding the connectors and instead using screw terminals or similar for direct connection between cables. My powerstrip is configured this way, without connectors, meaning the one end of my power cords are connector-less.