Never used one but I've seen the design for them before so they must work. Personally I just either drop the bottom hook off of the high low or tie an extension on to my weight to raise the rig, but I like to keep it simple and less visible so a float just doesn't appeal to me. Like Greco said try it and let us know, may be the next best thing.
http://s-media-cache-ak0.pinimg.com/736x/53/b8/41/53b841e6b2e825cfeb24b3665bc21009.jpg
ETA: Google image search Santee rig both styles are also similar to what you are talking about
http://s-media-cache-ak0.pinimg.com/736x/53/b8/41/53b841e6b2e825cfeb24b3665bc21009.jpg
ETA: Google image search Santee rig both styles are also similar to what you are talking about