Having read all the posts in this thread, I can say that all failures in tiller tines mentioned above are due to incorrect heat treatments of the tines. This incorrect/improper heat treatments are done for 2 reasons; 1- lack of good knowledge of heat treatment methods 2- intentionally improper heat treatment (to sell more tines as spare parts). If even Landpride tines are broken when they hit a small stone of Egon, then somethings wrong there.