In response to the idea of using 10/2 romex, there are one or two companies that are doing very large awg solid-core speaker cable like this. However, in my testing, I have found that the awg of the solid core will dictate the frequency response. Smaller conductors (such as 22awg) will transfer high frequencies but not low. Larger conductors will transfer low frequency waveforms well, but not higher frequencies. When I tested using conductors down to 18awg and 16awg, I found a roll-off of high frequency response. It become very "low fidelity" and I also found that there was a boominess or "blare" in the lower midrange. (solid-core silver may be different, but then again, silver has it's own problems).
If you look at the Audioquest Midnight, you can see that it uses a combination of 3x17awg, 2x19awg and 2x21awg conductors to support the full frequency range. The Type 8 uses four different conductors (16/18/19/20) to support the frequency range.
One note, if you get the Type 8, I would not recommend doing a bi-wire configuration because you are splitting off two of the conductors away from the woofers. With this cable and your speakers, you want as much conductor for the woofers as possible. You could, however, get two sets of Type 8 speaker wire and use one set for the lower/woofers and the second set for the mids/highs.
I have read a lot of "raves" about the Duelund 16awg. I did take a look at it. It uses oil/silk fabric wrap, which is excellent for dielectric, but it's still just stranded copper. I haven't tried it, but I would suspect that I would still like the Audioquest Type 8 better than the Duelund. I have used very expensive OCC copper STRANDED Furutech cabling, and it still doesn't sound as good as low end solid-core (it just doesn't sound right in my opinion).
