Thanks, everyone, for the feedback.
Before posting yesterday, 1Up was under consideration, but I recalled that some previous threads included negative comments about their customer service (especially compared to Kuat.)
But the replies here led me to give them a second look (literally, that erector-set design is sort of appealing, and maybe offsets the blandness of the 20 year old Lexus that will be towing it around.)
Truly a first-world problem...
So the CFO (Ms. Torquer) signed off, and 1Up it will be.
And I'll bring my customer service complaints back here if things don't work out.