Last I looked at the Thule site they didn't have anything that fits our vehicle. But another thread covered it and in the UK they have a nice low profile version called WingBar Edge - I think that there is an equivalent US version with a different name but not 100% on that.
So I ordered these Turtle bars off Ebay for $167 but, the seller said they had a supply issue and canceled my order. I'm now thinking about these other ones on Ebay for $129.99. It's not that I'm cheap but the Thule for 500 seems a bit high especially when I'll only use them 1-2 times per year to hold a cargo box. Anyone with cheapo Ebay crossbar experience?
Picked these up at Harbor Frieght for $55 after a 20% coupon for my wife's Rav4. Thought I would try them on the stelvio, they work. I can rock them back and forth a bit due to the rubber on the mounts but they feel solid. I cant imagine they could ever come loose. With nothing attached to them they do start to howl at around 45mph. I've had it up to 80 and the sound is about the same, nothing the radio volume doesn't fix. I still want a more sleek looking set that doesn't extend over the roof. I think these will fit my needs if I need to carry anything. $445 less then the Thule.
Update! Although these work I think they are made more for the raised side rails. I now use these on my wife's Rav4 and they are very secure. I did buy a set off ebay for $85 that are supposed to fit but I don't trust them enough to carry a Kayak at highway speed. I guess you get what you pay for.
I looked at the HF cross bars and walked away. They are designed for raised rails. I also measured and in their most closed position I felt they would barely grab the flush rail on the Stelvio. I would expect that if you tied a large item to them the wind might pull everything off (that is, the load and the cross bars too).