One person discovered that the ramp they had purchased did not work on their model RV.
This points out the importance of testing and confirming that your "Emergency" equipment will actually do what you expect on your RV.
It doesn't make any difference if it is a ramp or folding ladder or an "X" wrench to get the lug nuts off a wheel if you get a flat, or some electric meter or other test instruments.
It's ALWAYS better to confirm you know how to use the tool and to confirm you have the strength if needed or the necessary knowledge to actually use the emergency device.
I learned this the hard way with a "bottle" jack that was too tall to fit under the axle of my Class-C RV.
I remember when I first started to drive my dad told me that before he would lend me his keys, I had to use the factory "lug nut bar" to loosen the nuts. Then figure out how to assemble the "bumper jack". Get the spare out of the trunk, remove the tire from the axle then put everything back where it belonged. I probably spent an hour working on it the first time but I did learn how to do every step correctly. ( he let me know if I was doing something wrong a\or in an unsafe manner ).