Weight Distribution Hitch Needed?

[Stretch]

I've seen the calculator at https://www.ajdesigner.com/apptraile...utionhitch.php

Some of the numbers I just don't know or can't find. But inputting known numbers such as tow vehicle weight and manufacturer's towing capacity, along with the TrailManor weight information, shows well within "green" across the board for both Weight Carrying and Weight Distribution.

So given that, is a Weight Distribution Hitch even needed since these calculations are showing essentiallly the same? It looks to me as if there's no real benefit.

Tow vehicle would be something along the lines of a late model full size 4x4 half-ton V8 pickup truck with 9k plus towing capacity, approximate weight of 5500lbs, with factory installed towing package.