San Diego does not have length limits for folders. Neither the state nor the city have length limits for fixed blades, but you are required to carry a fixed blade plainly visible on your belt. Going out with a large fixed blade on my belt draws worried glances from passers-by. So if I want a large blade, it'll be a folder. So, do I want one.
It depends on what I'm doing that day. If I'm out and about town going to stores, or if I'm working inside the house, then I want a nice short handy blade of about 3". But if I'm hiking in a wooded area near my house or working in the back yard, a Cold Steel Pocket Bushman with it's 4 1/2 inch blade is nice to have and easy to carry. Closest thing to an actual fixed blade you can carry.
But then there's my Luzon Large with it's 6 inch blade. I mostly carry that because it's FUN.
Quiet said it in fewer words.