Thanks for your reply. It appears to me that the YL's would be ploughing anything from 10 to 13 or 14 inch furrows commercially, and as far as I know the shares were the same for all of them, hence the different width hinges that would be left. Surely there must be a best size to leave uncut. I used to find that 42's in stiff clayey loam would just lift the whole furrow and instead of turning it just shove it sideways, often rolling back in if pushing uphill. Like you though I couldn't beat 57's in hard land, and because they left a bigger hinge I found them pretty good all round. Only trouble was I only got what I was given and if the local dealer had 44's, that's what I got!!I use 44's predominantly, but I do like 57's. I tend to use 57's when its stony/hard (which I was told they were developed for) as they're more forgiving when in the ground. Sometimes I cut the wings down on 44's, sometimes I don't....I can never decide if it actually makes any difference despite the theories! ...deep down I think Ransome would have already chopped the corners off if they made a better job! I don't have any problem getting hold of both 44's and 57' although they're are more 44 repro's about, which work fine.