I’ve got the Ozone Wing Belt, similar design to the WIP. I use a maillon rapide karabiner for the board which slides along the webbing at the back, wing attached too at dyneema attachment point on front. The hook is just narrow enough to fold over when lying on the board, mostly I push to one side. Comfort wise it’s fine when hooked in, but not like a fully featured harness. Enough for me and minimalist design is perfect.

I have the ozone belt, which is very similar and I really like it. I hook my wing to it and ride with it higher up (over my belly button and over my impact vest). Then I have a waist belt for my board leash lower on my hips and below my impact vest. I really enjoy having my hands free from leashes and this one looks like a good one! The Ozone one doesn't seem hefty enough to put my board leash on as it just has a pigtail knot attachment. I like the D ring on this one.