Mother was right

Marks & Spencer jeans

As befitted a respectable middle-middle-class English family, my brothers and I were kitted out almost entirely by Marks and Spencer - from underwear to gaberdine coats and everything in between (except shoes, which usually came from Clarks). There was, as my mother well knew, no arguing with the quality. Most of what she bought me there I would outgrow before it wore out.
By my mid-teens, of course, I had outgrown the store and its stolidly conservative wares in another way.
Occasional trips back to England had me cruising M&S, and buying the odd item of underwear, but mainly for old time's sake. Nothing else of theirs appealed one bit.
Then in 2006 I went to visit E, and finding myself in need of a pair of jeans, bought some black ones for 20 pounds at an M&S sale. They were extra-long, bootleg, super-stretchy, with a lowish, but not excruicatingly low, rise. I didn't care for the naff red embroidery - a couple of linked hearts - on the back pocket but it only took 10 minutes to unpick.
This morning, six years later, I put them on again.  At some point between then and now, I took them in down the side to make them skinnies. But they're still long and stretchy, and still black - the most comfortable, good-looking jeans I own.
What on earth will I do if they ever wear out? Am I too young to hope that I'll wear out first?