They are expensive, but they hit hard, and don’t wear out. I had others and after a while they would wear through the hardening.
Maybe there are cheaper options, but they are still first class.
Expensive? Price a jewel for a bolt gun? IIRC, and this is no flame on you, just comments, a milazzo( probably a POS in Twigs mind too) was about 180 in the late 80s or early 90s IIRC.... means prices have not changed much in one way.
I"m all about a cheap RRA or maybe even a La Rue these days too, for most things, but I go into that knowing I will have to shoot them some, and then pull em apart and tweak em a bit. I'm ok with that for the most part for the savings as I generally have more time than money.