I’ve got a 6′ folding ramp used in my BMW Gran Tourer.
I use it for my heavy pride powerchair. The only problem is the angle is a bit too steep for the centre wheels so sometimes it gets the front wheels on the ramp and the centre wheels just spin as they are off the ramp. The solution is to go a bit fast at the start, get the wheels on to the ramp then stop and turn the speed down.
I use a number of bungee cords to secure the ramps in the car otherwise the bump and rattle constantly.
The ramps fit into the boot area without folding any of the rear seats, so if you’re buying some make sure they fit in the back.