The termination on my backstay is a Norseman - I did it myself and it's been fine for 20+ years. The only caveat is to make sure one of the outer strands doesn't lay in the slot in the inner cone. Not sure about the headstay - came with the Furlex. Probably Norseman. Also fine after 12+ years.

Recently redid the lower lifeline with the Hayn fittings that don't use an inner cone. Much easier to work with. Only downside from that job has been the new wire. The forming lubricants leeched out of the wire and stained the deck.

Don't think there's any choice for reliability. All seem good. But, follow the instructions regarding use of sealant and thread locker. Not a place for shortcuts or saving $5. I know of folks that have scrapped the whole fitting because of thread galling on tightening. Stainless seems almost as susceptable to this as monel. Not pleasant to have to cut a piece apart to remove it. It's happened with propeller nuts on submarines, where the nut weighs 1200# and includes internal hydraulics for advancing the propeller - expensive (and time consuming)!