Why are we always trying to survive? If things go wrong, I for one plan to live as comfortably as I can. If a knife can play a role in this good; if not, there are other tools that can help.
Survival knives are a genre not a function. All knives can help you survive. We all use some form of knife to survive every day (go ahead try to eat that steak without a knife). But, a "survival knife" is a type of knife exemplified by the RAMBO knives. In other words a survival knife is a knife like RAMBO's knife, in the same sense that a Bowie knife is a knife like Bowie's.
Its hard to say whether you are looking for a Rambo-like knife, or a general field use knife (a.k.a. camp knife, combat knife, trail knife, field knife, etc.). There are plenty of good general field knives. But, don't go by the name, its better to choose a knife based on your skills and requirements.
The Randall model 18 for example is a very good "survival knife." but, it was originally designed to cut through a plexiglass windshield, while carrying some perscription stimulants and pain killers in the handle. The hollow handle was a big plus, especially when the goal was to ensure that aircrew had something on their person when they existed their downed aircraft. The knife would either be attached to what they were wearing or in their hand when they existed the aircraft.
On the negative side, the model 18s sawback is far less effective on wood, it has a weaker blade handle junction than a full tang knife, and the round metal handle is less comfortable then a more traditional handle. Weaknesses, no not really, just some of the tradeoff that we will encounter with every knife we look at.
So forget the name and choose something that is best suited for your requirements. The humble SAK is usually a good basic choice for most.