My opinion without scientific back-up,
The trailer won't sway the bus, and if the trailer starts bouncing around hit the controller a little to provide a little drag.
Try pulling without it first to see how it does, if trailer bounces around too much, address that first, (loading, alignment, tongue height, etc.) Then if you still would like one, go for it and get one that makes you feel better

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I'm sure there is far better info out there that what I'm telling you so maybe somebody will chime in.
2 cents