When I bought my new 55 400 h Lexus charged me £200 to remove the bars and replace with those covers.
Unnfortunately I ended up with water running down the inside channels and Lexus said it caused damage to some of the electronics.
The car was taken back after approx 3 months and swapped for brand new one a year younger 56 with better satnav etc. I was pleased!
I doubt that it was damaged by the water ( the old story of check vsc ,check hybrid etc. see other old posts), but I was plagued with water in the boot under the floor which happened again on the new 56 one. They said the reason for the 55 car leaks was 'cos Lexus didn't seal the holes with silicon and couldn't blame me as they had done it ..for £200! They sealed them up second time round!
I am not certain whether the roof plates were entirely to blame on both cars as I eventually traced another leak into the boot from the rubber grommet on the top lip under the boot door.
I siliconed that and the leak stopped.
So this is just to say watch out for leaks in the boot!
BTW, I asked the Lexus garage what happened to the 55 car and he said...they scrapped it as they couldn't find the fault.!!! £45K worth of scrap !! Wow.
BUT I found out what was wrong as it happened again on my current 56 car It was a weak 12volt battery! I went out and bought an Optima yellow to DEEP CYCLE battery and the problems went away for good!!! But LEXUS won't be told!
I believe Tesla had the same problem with their Model S and swapped to a deep cycle 12v battery. Problems solved!
End of rant!!!!