Well, guys, having decided the day we bought our TT to have an 'equalizing' and 'sway control' system style hitch, our rig handles great in cross winds and blasts from 18 wheelers. Hardly ever feel a twitch. Don't know what it's like to compare to a 'without' rig, but I'm thinking I don't wanna find out.
http://www.equalizerhitch.com/productinfo/
I guess most 5ers don't have much sway problems in high winds?