Update: I ended up purchasing a brand new pair of 2CE Sig IIs. The dealer received them just this week, so they should be the latest and greatest iteration. Luckily, I was able to negotiate a price based on the $2700 MSRP (Vandy now lists them at $2999, and at least one dealer is asking even more (?)).
Now I'm impatiently awaiting their arrival.
I almost went for 3A Sigs, however, I'll likely be moving in the near future and my system could end up in a smaller space, so had to take that into consideration.
Also bought some AQ Type-4 cable per the recommendations here. I plan to terminate it with the standard 1/4" AQ spades for now. I just question how well they'll crimp onto those rather small-gauge wires. I suppose I'll have to reinforce the crimp with some solder.