EDC - folder, easiest to carry, period.
SD - proper training - if you have that, any weapon will do, modern folding knives are not as strong as FB but by all means strong enough to handle such situations.
Concealability - depends on the overall size of the knife, small = easy regardless of fixed or folder. also depends on what you're wearing, if you carry a backback anywhere you can conceal an axe if you choose to, if you're wearing shorts and a T-shirt it's quite obvious the folder has the upper hand.
Survival - proper training again - any knife can do if you know how to use it and if you know it's limitations. I have a lot of experience in those situations and I prefer to carry a multitool and a folder, it's lighter and easier to carry. wight is a huge factor.
SD - proper training - if you have that, any weapon will do, modern folding knives are not as strong as FB but by all means strong enough to handle such situations.
Concealability - depends on the overall size of the knife, small = easy regardless of fixed or folder. also depends on what you're wearing, if you carry a backback anywhere you can conceal an axe if you choose to, if you're wearing shorts and a T-shirt it's quite obvious the folder has the upper hand.
Survival - proper training again - any knife can do if you know how to use it and if you know it's limitations. I have a lot of experience in those situations and I prefer to carry a multitool and a folder, it's lighter and easier to carry. wight is a huge factor.