Decided to check my SM+ for foreign bodies this morning as I haven't done it for, hmmm, months probably. I was rewarded by a fair number of stones and glass shards, including a flint that was 5mm long and fully embedded in the front. Gawd knows how long it'd been in there but I was amazed it hadn't already caused an UDE.
And that, ladies and gentlemen, is why I'll be replacing the tyres with another set of SM+ ready for next winter*. I don't think many tyres would withstand that sort of attack, and give such a happy outcome to some shocking complacency on my part.
As for fitting, my 26x1.35s weren't especially difficult. I've heard the theory that the thinner 700C tyres can be a be-atch, however.
Archie
* The rear tread has gone and the tyre's squaring off now, so I won't push my luck any further!