My car is the same as yours barring the 4 wheel drive, but I've got a factory fitted Brink removable tow bar. When reversing, the parking sensors kick in when there are bikes on the back, not a major problem and it hopefully makes me well aware. It does look a bit of a mess on mine, especially as the plate with the electrics on has been bashed a t some point. I'll put a little pic of it without it's cover on, defo looks a bit crap.
Anyway it seems to work well, I bought a 4 bike Buzzrack buzz quattro rack, it's solid as a rock, but it's a couple of kilos heavier than that Thule one you have, still, it was only £250 and our MTB's are pretty light anyway. We went camping in the summer, roofbox full, bike rack on and never bottomed out. Car pulled like there it an empty car, totally effortless. Got a touch scary when we got on the Isle of Wight ferry and were ushered up the onboard (very steep) ramp.
It still doesn't seem right having all that weight hanging off a piece of metal though.
GT 3.2 V6 - Q2, KONI FSD & EIBACH PROKIT, GTA REMAP, MICHELLIN PS3's, BMC CDA
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