I bought one (154CM version) specifically because I wanted a large folder that could be carried with either a pocket/belt clip or in a sheath that could be mounted to a pack via MOLLE or similar attachment method, acting as a backup to a fixed blade. I previously bought a Ka-Bar Mule and Benchmade Adamas for the same purpose, but found a price I couldn't pass up on a CSAR-T and took a chance. I'm very impressed with the knife (and sheath) and feel I can trust it in its intended role, but it's entirely possible that it will never see any actual cutting use.
MT_Pokt raises a good point about it not being a good backup without another knife for certain roles, although I would qualify that by deciding what the role of your primary "survival" knife is. Some folks think that survival entails everything from cleaning game to food prep to wood processing to combat, and no, a CSAR is not going to be great at some of those tasks, but the argument could be made that any fixed blade knife for which the CSAR is an appropriate backup is likewise probably not ideal for some of those same tasks. So, consider what your idea of a survival knife is, look at your primary knife, and decide if a CSAR can adequately perform the same tasks if the primary is lost or damaged.