Nemrod is right, a US Divers vintage doublehose, with proper service is more reliable than any new regulator, even in most freezing conditions. Only a truly environmentally sealed regulator would be better in the most severe freezing conditions. Still, except in very shallow diving, I always have a backup.
For my most critical or dangerous OC dives, my double hose is the primary and either an environmentally sealed Conshelf or Poseidon Cyklon 300 is the backup. I have yet to see anything safer. I have trusted this combo way beyond 300 feet many times.
Also, I almost always carry my deco gas with me (I often dive triples) rather than relying on stages hanging from a line.
Deep diving doesn't scare me, diving beyond my equipment, training or experience (or with an instabuddy) does.
For my most critical or dangerous OC dives, my double hose is the primary and either an environmentally sealed Conshelf or Poseidon Cyklon 300 is the backup. I have yet to see anything safer. I have trusted this combo way beyond 300 feet many times.
Also, I almost always carry my deco gas with me (I often dive triples) rather than relying on stages hanging from a line.
Deep diving doesn't scare me, diving beyond my equipment, training or experience (or with an instabuddy) does.