I have the factory cross bars and the associated mounting rails. The factory bars put the RTT so high it interfered with low flying aircraft. It also puts the CG of the vehicle a bit on the high side as well. So I ended up machining six mounts and incorporating elements of Front Runner mounts to make a really low profile mounting system. I use the Thule bars for the RTT, just because it is much faster to mount that way. I fabbed up a hoist system in the hanger so I can pull everything off in 10 minutes. You can mount some of the tents directly to the Front Runner Slimline. This way, however, I can also store one RotoPax can under the tent mounts (out of the sun). The larger wind fairing is also one I made from ABS sheet, patterned after a Yakima fairing, just bigger. The lower one is the Front Runner one supplied with the rack. Doesn't make much noise at all. Now, I didn't want to make the rack too low, since I mount long stuff, like poles and equipment tripods on the underside of the rack.
Now I am supposed to get a new 2022 Defender 90X, but it seems to be stalled in the port since the 25th of January (I ordered the bloody thing in August). I may eventually get it. I ordered it with the Expedition Roof Rack. So my upcoming dilemma is, which one works better. I may end up doing a similar mounting fabrication, since the one Front Runner sells is rather BS and hugely expensive for what it is. Then again, the factory rack may work after all, if I ever get it.