Farmer's bars are way the hell easier, provided they're not incredibly thick and rubbing against your legs.
Honestly, I wouldn't worry about form with dumbbells. 47.5 kilos/hand is a joke if you're actually wanting to do this for strongman competitions. I'm not saying that to be an ass, but just to give you perspective. I mean, most lightweight (231 bodyweight and under) comps have 100 kilos per hand, for about 100 feet with turns - and even that's light.
Hanley, when you turn, try putting the right hand slightly forward of the left (if you're turning left). This way you can push the left one into the right at the end of the turn and straighten them out.