I’ve been using my saris bones 3 on my 08 plate Mondeo. Been to south of France and back and various smaller trips without issue. I had no idea there was a suggestion it wouldn’t take the load but it’s been fine despite my ignorance.
I put the two top straps on the boot where it hinges (straps need to be quite long and need to be positioned to avoid the rear wiper), two on the sides of the boot and then the bottom two, I attach together (in a sort of ‘V’) to a metal loop in the centre under the bumper. I can’t picture if this is part of a tow bar that’s under there or not though? Once it’s all pulled tight, it doesn’t feel like it’s going to go anywhere.
I guess the issue is the plastic bumper? I wouldn’t attach the bottom straps just to that. This metal bit underneath though seems a solid enough anchor point. It’s seems fine but maybe I’ve just been lucky?