...is it just nice and tidy with likely no sonic advantage?
You really just answered your own question here.
Cable is cable is cable is pretty much the rule. 16 gauge is 16 gauge, copper is copper. If you change up metals, to say, aluminum, then you are doing something different, and not good. If you go to an exotic metal, you may get a slight improvement over copper, but not one you're likely to hear. And, of course, going from a lower gauge like 24 gauge, to 12 gauge is a pretty big overall difference, but still likely not noticeable on such a short run.
All of these parts and pieces you can buy yourself. The most notable is the speaker pants/boots. Since most DiYers don't bother with them.
Looking online, a decent pair of banana plugs might be $1 each. So, $4 for both ends. Add the pants at $1 each - $2 total. Plus, speaker wire at about $.50 a foot - $3 for a 6 foot length. That means you can build this for $9.00 for a 6 foot length plus some time. I expect someone making these by hand, but doing a lot of them, is not paying as much as I listed, and can probably put together a set in 10 minutes or less. Maybe $8 or less in materials, so about 100% markup if being sold directly.
It's not a horrible level of pricing, but it isn't going to actually make anything better if you're already using the proper gauge cabling for your speakers and lengths.