I've towed a lot of different trailers since 1968. Most of them just on the ball. No WD hitch, no sway control device. Many of them at speeds that the folks here on RV net would claim I am a reckless danger to society.
My experience is, a properly designed trailer, correctly loaded with adequate tongue weight, hitched in a level attitude, on a tow vehicle that is a good match to the trailer, will tow correctly with no sway.
In other words, get the fundamentals correct first, then add things like sway control and weight distribution hitches to fine tune the entire set up. IMO.
