They work well, but I have to made some modifications due to them touching the side of the roof of the car (even with the HiRise Spacers) on my Mercedes G550. Cannot fault the product for that, except that there are two ridges that seem to be designed in for strength but they are contacting the roof. If the ridges faced towards the outside of the car, it will be less likely to cause damage.
Rating: [4 of 5 Stars!]