I've used the Havalons for years but was always frustrated because I knew that there was an easy fix to all the broken blades. I also had one open up in my pocket on two different occasions. Try getting that out of your pocket without cutting up your hand!
Outdoor Edge fixed both of these problems with their new Razor knife. I've been using this knife on bears, lions, elk and deer and have yet to brake a single blade. Much better, and safer, locking mechanism that holds the blade in place and the slot that the blade rests in gives you an unbreakable blade but with the advantage of a razor blade that we all like.
i found them on eBay with 6 replaceable blades for about $35.