My CX bike chain has done 1159 miles, (1865 km) and it is still way less than 0.5% elongation. I decided I will chuck another chain on it anyway, to keep the cassette and chainrings in nice condition. This bike is used on all manner of surfaces, in the wet and cold and on salty roads. I was surprised at the distance it has done since fitting the previous chain in late February, but it has been my main training bike, and that has incurred some big mileages. I was surprised at how little wear is showing on the chain wear indicator. I guess chainsaw lube is the way to go, and never putting water near the chain when cleaning the bike or the chain. This is a 2 x 11 speed drive train.
So today, I bought 2 chains from Hopkinsons. ( <£13 each )