I used these when they came in packs with a headstock on the cover but when production shifted to Mexico thought they became more brittle and were short lived.I kept swapping between Ernie Ball,which felt heavier/stiffer and D'Addario which broke too easily.
When I noticed these were being USA made again I tried a set and have been using them since.I wouldn't be surprised if they were being made for Fender by D'Addario(those coloured ball ends) but the plain strings are not breaking at all,unlike the Dads.
Right now I think they are the best sounding strings at the vintage end of the spectrum available...
I find them just nicely bassier on the wound,with a feeling of mass about them but a nice pliable feel overall.... and they seem to last and last both tonally and physically....great both clean and driven...with all sorts of pickups...Fender,including Jazzmaster and original Widerange,Gibson Shaws,Minis,Dirty Fingers and vintage P90's...
A really good value string for those who prefer a more vintage toned sound....