I strongly prefer fixed blades but, as others have already noted, there are (IMO, stupid) legality issues. Would love to see the reaction on peoples' faces if I were to carry my #12 9" (#14 grind for you afficianados) Randall down the street of Denver or any other major city. Yet, in the mountains, it's perfectly acceptable, and that is what I carry. In the city, my Spyderco Delica fills the bill nicely, and is within the (again, stupid) 3-1/2" blade length limitation. That same Delica, however, would probably be deemed illegal in New York City.
Ah, the joys of knife ownership. The only thing worse, from a legal standpoint, is gun ownership.
But until we live in a country (geez, don't even get me started on the world) where everywhere has common laws on these issues, I will own and carry multiple things depending on the circumstances.
As far as expense - yeah, join the club. There are an AWFUL lot of really nice knives out there for under $100, and I have plenty of them. The Randall I just referred to would likely bring $1200 if I chose to sell it. Are more expensive knives better? Well, sometimes yes, sometimes no. But if you can easily afford to spend that kind of money, if you do your homework and get something of good quality that will maintain or increase its value, and if it makes your dick hard, I say go for it.