I agree with this. Although I'm driving on some fairly decent roads in San Diego, CA, USA. I drive a Jeep Wrangler which isn't a very smooth ride, and the place I went to get my empeg installed for me did a crappy job leaving the backend of the unit unsupported and bouncing around quite a bit. I drove for a couple of days before I had the chance to fix the installation (at least temporarily). And the only thing I noticed was the anoying clicking sound that the frame made as it tried to bounce it's way out of the plastic bracket that holds the unit in.

Eoghain