I'll add that my two economy tractor supply halters are 10yrs old and still going strong. They are the stiffer type, 2 nose knots. I use them as spares in my saddle or around the barn cause I know they won't get filched, lol. I also have a lead with popper and halter set by Silver Tip--like the Double Diamond brand--10yyrs old also and still great, though the lead is cheaper grade and is getting fuzzy. The stiffer ones also keep their shape better and easier to get on for that reason. I have an ebay
parelli knock off that's really flimsy, and when your horse tries to be extra helpful and stick his nose in before your ready you can get all tangled up, lol. Yeah, these things have been around a long time and Parelli even mentions he used to be required make tons of them in his FFA group in high school. I think he might have sold them even then for fundraising.
I think it's great that you've made insrux available AnrewPL. I've always wanted to make my own to pass along, but since I'm knot challenged I put it on the back burner. I'm going to make it one of my goals.