They are nice, but you do add extra time every time you drive. They make a big difference in driving control. You may know this, others may not. You can't just use any harness and take away the crotch harness the 5th harness that goes through your crotch area and through a hole in your racing seat we don't have and think you are safe. You will submarine under the belt. The DOT approved one has a break away strap on ONE shoulder that turns your torso and locks you in the harness and doesn't let you submarine since you don't have the 5th crotch harness to save you.. There are only two companies that have been approved by the DOT or use in a 4 point harness configuration. Those two are Scroth and Takata, both owned by the same corporation. Also, unless your manufactures car seat has been approves for "low mounting point harness attachments" you MUST have the attachment point of the shoulder strap AT or ABOVE the top of your shoulders. Otherwise the seat back can collapse and crush your spine. Just a heads up if anyone wants to look into a harness.