No experience with Equalizer, but drove quite a few thousand miles with;
- Reese Dual Cam HP
- Either a 1997 Tahoe or a 2004 2500 Suburban
- Either a 2001 (?) Thor 22' trailer or a (2003?) 29' Keystone Cougar that measured approx 34' from hitch to rear bumper.
Altered the Reese Dual Cam HP a bit when switching to the longer trailer.
In both setups, the effect was incredible: when driving through cross-winds or being passed by 18 wheelers, the push felt like it was trying to push one big vehicle rather than pushing the trailer, then the tow vehicle, then the trailer, etc. The Dual Cam HP eliminated sway in every instance where it could occur.
The only time it didn't eliminate sway was on a highway where I came around a corner and found a truck had just spilled construction debris. By the time I made it through I had two flats on the right side of the trailer (in the end, I was happy that was all the damage). Got a bit of tail wagging the dog effect, but I'm sure it would have been worse without the Reese Dual Cam HP.