Published at Saturday, July 28th 2018, 22:06:42 PM by Roseann Pennington. Knives. The blade length on survival knives is often the subject of debate. Most people should avoid the huge "Rambo" style survival knives. They are heavy and can be awkward to use for many of the tasks survival knives may be expected to perform unless you are familiar with how to use the knife. Many people feel more confident with long heavy bladed survival knives. Others feel survival knives with a long blade are too awkward for some of the tasks they expect survival knives to do.