Baseline:
Cheap Chinese folder- $10-15
RESULT: A barely usable knife or an unsafe POS, it depends. Most people feel they get their moneys worth, if barely.
An inexpensive knife- $25-$45 (CRKT, low end Spyderco, BM, Kershaw etc).
RESULT: Huge difference. The knife should function reasonably well. Most people feel they get their moneys worth. There is some satisfaction and pride in these purchases. Almost no buyers remorse or diminishing returns here.
Low to mid grade folder- $50-100, (Spyderco, BM, Kershaw, CS, etc.)
RESULT: Really big difference. Now you are getting very good construction and higher end blade steel. People are happy with these offerings, they get a good product that could last many, many years. No buyers remorse, and almost no diminishing returns on this class.
Mid to high end production folder- $ 125-250: (Al Mar, ZT, Fallkniven, Emerson, Spyderco, BM, etc)
RESULT: People start to see what the fuss is all about. These are nice knives. A person jumping from a $60 folder will immediately see the difference and understand why he paid so much for the knife. These are knives that you could hand to a total non-knife person and they would probably comment on how nice a knife it is. These are so close to high-end offerings that there is really no practical need to spend anymore for a superb quality folder. Lots of pride of ownership involved with this class of folder. Material quality, and construction, is top notch. Blade steel is near, or at the highest level available. The average person knows they paid a lot for the knife, but probably feel they got their moneys worth and would recommend them to others. Probably not too much buyers remorse if the person could afford it in the first place. Diminishing returns are more prevalent at this point.
High end Production folders- $300-500: ( CRK, Strider, Hinderer, etc.)
RESULT: These knives are the epitome of production craftsmanship. Everything (should) be tight, smooth and strong.
But, there is not that much immediate difference between this price point and the $125-250 price point.You could hand one of these knives over to a non-knife person and they may comment on how nice the knife is. If you told them how much it costs, they would probably be shocked and think you were crazy for paying so much for a knife.
You are not getting twice the knife for the money. Most of the cost involved for these knives are for things you cant even see; tight tolerances, warranty, prestige. Spyderco, Kershaw/ZT and BM make several knives that are more exciting, different, and fun than these knives, for a lot less money. Things you can see in other words.
A person going from a $60 folder may truly wonder why the heck he paid so much for a knife that may not seem all that great. The quality may be obvious, but not for the extra $300 they just dropped. The knife may have annoying traits, (Strider break-in), be much thicker and heavier than he is used to, (Hinderer), or may just seem plain and unexciting compared to his other folders, (CRK). There may be major buyers remorse.
Bottom line, buy what you like, with a design that appeals to you. Forget about the price.
Bragging rights only last so long.