I was looking to get a set of cross bars to mount snowboards/skis and luggage on top of my X5. I really like the low profile look of both the Whispbars and ROLA sets but I was not sure what kind to get, (I'm thinking the S46 whispbars but not sure on the ROLA system. I was also wondering if these have enough clearance for the Sharkfin and for the tailgate to fully open with things on top of the vehicle?