Spyderco makes knives for people who use knives. Their knives cut. They aren't sharpened pry bars or folding axes. They invented the tactical knife as we know it, top of the line steels, the opening hole for one handed opening, and the pocket clip. They are one of only two companies that put out fully serrated knives (cold steel being the other, and their serrations are poorly designed.) If the opening hole wasn't an excellent design to function as a one hand opening method, other companies would not be borrowing, copying or stealing the idea to use on their knives. It is fool proof. Spyderco is one of the few companies that put out the same knives with different locks (the sage, manix etc), different steels (endura, manix, mules, etc) and different grinds (endura, delica) to test them on identical platforms. They offer the most rust-proof stainless steel on the market (H-1) and offer the broadest range of knives for every taste, from the tiny bug to the manix xl. They make slipjoints and automatics. They regularly collaborate with well known makers and amateur designers and the listen to their end line user.
They offer knives in every price range and knives for users and collectors alike. They make knives designed for hard work and knives designed for self defense. If aesthetics are the number one concern in your decision to purchase a knife, then spyderco probably isn't for you. They are designed in the dark and function trumps form. They must be doing something right when other larger knife companies copy their designs to the tee. Benchmade and SOG both have endura clones and there is a reason for that. The endura/delica platform is a tried and true design that has been put to the test for decades.
Spyderco is one of the most versatile production knife companies on the scene today. They are not for everyone but that just leaves more for us