Thanks for the comments! I'm back from the trip, and washed off the accumulated road grime, swarms of bugs, complete coating of pollen, etc... Yecch... Wisconsin backcountry is nasty for cars.
The wheel paint is holding up fine so far. One new thought on color is that the black (on the shield) shows waterspotting much more than the aluminum (on the hub). So it's a toss-up which color is easier to maintain... waterspot-aluminum or brake-dust-black.
So I'll probably use aluminum for the front hubs to keep the same color scheme.
Also for whatever reason, the brake dust doesn't seem to stick as much to these wheels. I'm not sure if it's because of the fresh finish, or that I waxed them before installing, or that the open design lets more air flow through, or some combination. But I'm not complaining!
Overall a pleasant trip, mostly highway speeds (60-80mph, a few bursts to 90+), with some back-road asphalt curves near our destination to liven things up. Family on board, so I couldn't test the performance envelope too much.
I'm still happy with the wheel/tire performance after just over 1000 miles. The only new note is that on rougher road surfaces they are significantly noiser than I originally reported, but I'd say no more than my previous tires. I am also running them at higher pressure than my old tires which may be a factor.
I have yet to try them in rain so that's still an unknown.