The ones that people have used to this point, like the commonly available Thule, apparently have some drawbacks, chief among these is the windnoise I gather.
(Who knows, the ones finally called "Nissan" may well be Thule)
And they shouldn't be flimsy. They should be rated for 150 pounds MINIMUM.
The Nissan ones should not generate objectionable wind noise as one of our posters here, Chancie, is part of the test team and they have been working on them for some time. And she has said that the problems with the test units has been noise.
Many Other vehicles have cross bars that do not make objectionable wind noise.
So I expect them to be good.
Plus they said they would have them.
We can't let them off the hook on Everything!
Homer