I've had 5 punctures on the Randoneurs in about 2,000KM. I don't think it is the tyres, all the punctures have been very thin and sharp objects. Nothing else seems to get in.
One thing though, the tread is starting to get a bit worn, when do you need to replace a tyre? The tread is wearing down fairly quick on the top of the tyre which of course is the part that contacts the road. I would expect to get maybe 5,000KM out of the tyre (it's on the back - I am probably about 100KG and I also have a basket on the back with a bag which would add a few more KG). Can you run the tyre until the tread is basically all gone? Maybe I'll take a pic and upload it.
When that red puncture-resistant layer wears through they'd be shot, but I don't think the traction of this layer would be too good. I retired the Randonneur Crosses when this red layer began to show - 14,000 kms (not out). These tyres have been used by fixie riders with their passion for skid-stops. The Randos are some of their favourite tyres.
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