I rebladed my drill (750) spring of '07 with JD, Shoup and CaseIH earthen metal. 2 JD's, 2 shoup and the rest of the drill with CIH - they were slightly less money and made in Canada. With two seasons on them I can'nt really tell which is sharpest or dullest. I think the shoup are slightly duller then the other two, but I can't tell any difference between CIH or JD. I haven't taken the blades off to measure, but it appears there isn't any more or less wear on blade diameter either. I do plant in some pretty abrasive soils and rocks - doesn't help sharpness.

I have wondered, could a guy sharpen the blades (ya, alot of work), but it would help.