I computing a 25km-75km buffer in eastern Europe. On a 75km buffer turf.distance calculates a point as 60km away but the buffer of 75km does not extend to include the point. I am supplying unit='kilometers' to both. My database which uses sloppyarc seems to agree more with turf.distance. Do these two methods use different distance calculations? It's not documented what buffer uses as an algorithm only that turf.distance uses haversine. I am more concerned about consistency (For UX presentation) than complete accuracy.