Equipped.org's Gear section says:
"Many experienced woodsmen carry a knife about 4 inches long, give or take a little, for general purpose work (many also carry a second bigger knife, but the small knife is what is used for most chores). A survival knife can stand to be a bit longer, but not too much longer. You simply do not need an enormous blade for any job you will likely be faced with in the wilds."

Do you really think we need large knives to survive? I like my Becker BK10 Crewman a lot - its done everything I've needed it to do and its not much longer than 4".

You'll note that he didn't give any specific brand recommendations - probably to avoid angering the owners/manufacturers of the many many great brands that simply could not be mentioned in a looong list.