Yes, quite a few of us have.
Mine's a detatchable Thule with just a normal 7 way bypass for the trailer lighting, there's no need for dedicated wiring kits.
The relay only beeps if normal bulbs are used in the trailer board, use LED's and you don't get that annoying beep with the indicators!
It's quite easy to fit, remove the rear bumper cover and remove the crash bar underneath, the towbar replaces the crash bar.
There was a small cut needed under the bumper cover on my 4x4, you can't see it, just enough to get the ball located in the bar and to swing down the electric socket (it's tucks up when not in use)
With no ball fitted, you can't tell if a bar is fitted.
The only gripe is the main power supply for the bypass, there's nothing in the rear to run it so you need to run a wire all the way to the front to pick up it's power, but that's the same with the dedicated kits as well.