Distance racing is a big factor, some 5.7 sailors at our club bought the latest over the shoulder but with nappy to save some weight and a fair bit of money. They reckon it has made them faster sailors because they need to get back on the beach asap to unscrunch the family jewels. My wife and I have Magic Marine Revolution harnesses they have a yoke around the neck so straps don't slide down your shoulder, a spreader bar, covers over the buckles so they dont snag and come undone, leg straps that you can set and step out of we do a bit of 50-70km racing and have never been uncomfortable because of the harness. The downside of them is the cost and added weight.