That harness is a lot like the one my boys are wearing (the first pic). Our harness is made of soft but durable fabric, so it's very light and dries fast even after a swim in the lake.
In the second pic is Manu with his trailing harness. It is a T-shaped harness, so it's not as good as a Y-shaped one. The front part can go up on his throat if he pulls. Fortunately Manu doesn't pull at all (not even when trailing), so it doesn't matter.
That harness is a part of his trailing gear now, so I can't change it unless I absolutely have to. He knows what to do when he has that harness on.