I have to wear steel-toed boots for work, and have for almost 6 years now.  With all of my previous boots, the laces have just about lasted as long as the boot. (Usually just about a year) The latest pair I bought seemed to almost cut any boot laces I put in them within a couple months.  After buying a couple of replacement laces and not having them last too long, I found these ArmorLace Boot Laces on here with some pretty positive reviews.  So I decided to take a chance and see if these laces would work better.  Well, it's been almost 5 months now and these laces have done well so far.  There's some wear on them where the other laces were being cut, but it's not damaged these ArmorLace laces to the point of them failing.  In fact, I'm about ready to replace these boots with a new pair, and I'm pretty confident that these laces will still be around!

So, if you're looking for some high quality boot laces that are tougher than normal laces, these will definitely do the job.  They are stiff at first, but once you break them in they are just as flexible as normal laces. I was hesitant with their higher price, but I would have probably spent almost the same amount with regular replacement laces at the rate I was going.

UPDATE, November 2014: I wore the boots that I used these laces on for about a year at work and they were great, never frayed or broke.  I've been using them the last couple of years when I'm doing yard work on the weekends and the laces are still solid. They did get a lot less stiff with wear and tear and they do show some wear in the places they'd rub on the boots, but they are still as strong as when I first got them. I'm finally to the point of throwing out the boots. lol.  But you better believe I'm keeping these laces in case I get another stubborn pair of boots!