My roof rack holds recovery boards, I have them in case I ever get trapped in a ditch where one of tires cannot have grip to come out. But I’m sure 99% of time, quad motors on each wheel can come thru. I also intend to put bike up there in the future. I can easily put the recovery boards in the frunk, but it look cooler up there tell ling people you go up mountain but you are actually a city boy in flat Houston.
Range-wise, I don’t feel any effect since item is small. However, when I first install cross bars with recovery board mount, I can hear wind whistle; therefore I put the them in the rear and whistle went away. You can have up to 3 cross bars.
Added 3 inches also created a challenge to enter building garage or basement garage. Fortunately, I can frop suspension 3” to get in most garages.