I have come to notice that there are certain Spyderco that occupy a sort of "sweet spot". What I mean is, they are nice but not so nice or expensive that you won't carry them when you might lose or damage them.
Here is an example, I recently went hiking in Starved Rock IL. I live in Indiana where it is legal for me to carry pretty much anything I want. I wasn't sure about Il. laws so I didn't want to take a large blade like the Manix or the Military. I also didn't want to lose it since I was going to be all over the place. It was hot when I went there so I wanted to wear shorts and I didn't want to have them weighed down by a heavy knife like the Manix.
So all this was taken into account and even though I own some nice larger and more expensive Spydercos, I ended up packing the Centofante 4. I also have a Delica 4 CE that I was going to take. These are nice knives but they are on the small side and not expensive. If I lost one of these, I wouldn't worry as much as if I lost my CF Mili. They are also light weight and carry easy even in shorts or thin pants.
I end up really using certain Spydercos more than others because I carry them more. It is stange because it is a case where less is really more. Less weight and less expense equals more utility.