Windsurfing Harness

Try on in the shop before you buy. Comfort, comfort, comfort... Bit like shoes and boots. Never know until you try. Started sailboarding with a seat harness. Was clueless and it was what the shop had that fit the budget, was comfortable. Purchased when just able to get into the footstraps, but unable to do a planing jibe. A few years later learning to wave windsurf and needed to replace the harness and tried a waist harness. Liked the waist harness. So I went and purchased one. Haven't used a seat since then (1997). No good reason outside of personal preference.

A harsh and maybe inappropriate comment. Looks don't matter. It's the attitude. I think it was Roberto Ricci that said, "to be uncool is the new cool". Back in the late '90s or early 20's. Robby Naish on Maui after a photo shoot or promo at Kanaha noted when asked who was the best or new hot or whatever something windsurfer out there. He pointed to a skinny local newbie grommet coming out of the water with the biggest smile on his face.

I use a Severne CMR, although its designed as a race harness due to having some fractured ribs I cannot use a waist harness and the CMR has a fairly high hook, which I like.
It depends a lot on your sailing location, would you be in and out of the harness a lot due to waves or gusty winds compared to using it in say an estuary where you might be more Freeride sailing with more constant winds. then I would use a seat harness.
Seat harness's put more power from you into the board and are better for racing and can be more comfortable than a waist harness but its personal preference too.