I have the Nitto B135, their 39cm model... which measures 39 at the ends of the bar, but since it's flared the hoods are only ~32 apart. I absolutely love it. I ride on gravel roads with that bike, but it's mostly a brevet bike. I don't like wide handlebars, feels like driving a bus. My mountain bike has really wide bars and I keep thinking about cutting them down, or buying some narrower ones. I guess on a gravel bike designed with the wider bars it might handle better but my bike has bog standard "endurance road" geometry so I doubt it'd like the feel of wider bars.