They're fine to use on the road. Every single MSA & FIA rally car has a proper buckle with 5 points minimum on both seats, and they're all road registered, MOT'ed & legal. Total *******.
They may not all be legal for type approval, but retro fit isn't a problem. And the buckle would never, ever fail. So when would it even bear any relevance in an insurance claim?
I think this all started because seat belt manufacturers call the normal buckle up ones 'road harnesses'. But this is more because 5-6 point harnesses with proper buckles are a total PITA to do up all the time, not ideally suited for road use.











