That is all user preference to be honest. Some people like to see their rear bumper (to view items on the back, we have one of those fold down cargo trays and we like to be able to see it). Some people dont care to see the first 5-8 feet behind the RV, etc. Whatever works best for you. Experiment with it and see what you find best suits you.
2019 Ford F250 Lariat 6.7 Powerstroke
2020 Cherokee Arctic Wolf 287BH