The first good knives I got into were Spydercos, and I think very highly of them. They have great, ergonomic designs, and cutting edge steel options. They're also pretty competitively priced. In the past year, I've evolved my tastes towards simple, clean, robust designs with less flash. I've winnowed down my Spyderco collection and exploded onto the CRK scene. Right now, CRK is by far my favorite knife company. They are the highest quality, best constructed knives I've experienced. They also hold their value like nothing else. You can recoup almost all your expense on the secondary market, in the case that they aren't for you.
Essentially, at the $250 and below pricepoint, I think Spyderco has the best designs, steel, and quality available. Above $300, CRK's are where it's at.