Sub-frame connectors... Please build them correctly!

Take this for what it's worth. My Dart had bolt on style subframe connectors. They went front to rear and also bolted up through the front seat area. When I would jack up the car I could hear the them shifting slightly. I figured if they were shifting how well could they be working? I just as of two weeks ago went with weld in style sub frame connectors that followed the contour of my floor pan along with torque boxes front and rear. It's made a noticeable difference in the overall stiffness of my chassis.