I have 16,000 mls on this set,I turned the front sprocket around at 13,500 mls.(ish).Had a look at it last week whilst sprocket cover was off and all looks fine and hardly any wear on the load side.So hopefully I will get another 10,000 mls.out of it,but need to start having a more regular look at it.If I can get 25,000 mls out of it I will be happy.My useage has been mixed on this chain set,at a guess 40% motorway,50% country lanes and backroads,10% town.I have a Loobman chain oiler on it,which has been no bother until last month when the button started sticking,removed it and a good clean sorted it.