What are the main features and benefits of a 5th wheel?

More interior space with a shorter combined length. Fifth wheels do not have drawbars like a caravan and some of the fifth wheel overlaps the length of the tow vehicle. The Flagstaff 23 also has a sliding wall that extends the living area. An Ultima 27 has the combing length of many 23 foot caravans with more interior space than the equivalent of a 35 foot caravan once the sliding wall is extended.
Easy to hook up. One person can in most cases easily hook up a fifth wheel. By simply looking out the back window of the ute you can see the hitch and the pin.
Far less sway and better handling than most caravans.