There is no perfect survival knife
The most important part of a knife is the steel used on the blade, high carbon, high carbon stainless 420HC, AUS 8, 440A, 440B, 440C, 8CR13MOV, VG10.
Second would be the size of the blade, maybe some people might find a 6" blade long and bulky and prefer a 4" blade. Another will be the handle or scale material; plastic, glass reinforced nylon, Zytel, micarta, G-10, stacked leather and stag. The characteristics of the knife will tell you if it's the right one for you.
There is no perfect knife, all have their uses so choosing one sometimes might be difficult. A survival knife doesn't have to be expensive, but it has to be reliable. It also will depend on the area you will be using it, is it a dry climate, humid, salt water, woods, dessert, mountain, plains.
I have purchased many knives over the past few years, from cheaper Moras to the more expensive Spydercos. And I have found out that I sometimes prefer some of my cheaper knives over the expensive ones.
For a fixed blade under $100 I would look at the SOG seal pup, fixation bowie, field pup. Buck has the special and the vanguard. Old timer has the mountain lion and deer slayer. Cold steel has the GI Tanto. Kabar USMC fighting knife. Glock also has a good knife.
All of those I have mentioned are bigger knives that might come in handy, and you won't worry about abusing them or losing them. So once you pick your primary knife you always need a backup knife, many people choose a smaller size knife many times folding knives. I do prefer fixed blades over folding in a survival scenario. Fewer things will go wrong with a fixed blade and can take much more pounding than a folding one.
There are many choices out there also. You have the Mora's many models under $20, the cold steel lite hunter, roach belly, Finn bear. Old timer sharpfinger, Kabar Becker, Buck paklite skinner, Buck 103 skinner, Gerber warrant, Gerber epic. Case makes excellent fixed blades like the Ridgeback wood hunter.
These are just a few examples of what is out there. If you can afford a custom-made knife go for it, as these can be tailored to your needs. As for me, I carry a SOG seal pup with a Boker Arbolito 504 as back up. I also carry a Lansky triangular pocket stone for sharpening. These are the ones I choose to have as first call out in the wild.