i have 113,000 on the highly modified evo motor--- all on mobile 15-50. extreme hi speed long distance touring thatd be 85+ in the saddle all day-- i aint talkin 8 hrs either.. only failure--lol an that was my fault a jims lifter wheel froze up at 56,000 miles on em. in fact wore 35% of the lifter wheel off. galled the exhaust cam lobe just a teeny bit-- i didnt change the cam that was 14,000 miles ago...... so yea -- i like mobile one