I have the first one on your list, spring broke after a couple weeks but in a place that was fixable. These are fun but bound to wear out quickly because of moving parts and cheap build quality (not to mention addictive as well!). A Novelty at best, not for hard use. Hope this helps. edit: I store this knife with no tension on the spring by opening it against paper or cardboard so the blade is "loose" hopefully prolonging its life.