I have a 44 inch First Choice tiller and it works fine in my clay soil. I paid about $900 for it two years ago. If I had it to do over again, I would have opted for the 48 inch model to make sure both tire tracks are covered.
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I have a Ferguson 42" on my 2000 BX2200. I paid $1200 in 2000. I have had no problems at all with it. I have tilled gardens, done landscaping, and till up ground into fine topsoil when I expanded my driveway and put in my deck. I don't have any tire tracks after I till as the dirt covers them. Just rake in the sides and there are no tracks.