My bike is a 59, I’m about 6’ 1”. When shopping, the LBS owner who is about the same size suggested the 56, as that’s what he prefers. I tried it, but it did have a toe overlap/strike issue, I took it on a 50 mile road ride, but still didn’t care for the toe strike, even though it wasn’t an issue when actually riding. But this is also a gravel bike, so I had to consider occasional low speed turns with more turning of the front wheel than it typical on the road. So I chose the larger size.