I have an original Endura and Delica, both with the plastic clips. They're almost 15 years old now and have held up pretty well. I probably carried each of them for at least a year's worth of days without breaking the clips. (Of course, the newer models are metal clips.)

Now I carry the Spyderco Caly 3, plain-edge with G-10 scales. It's a bit expensive (I paid $75 a few years ago), but it's an awesome knife. With more of a flat grind than the saber grind of the Delica and a little "convex edge" sharpening work, it push-cuts better than anything I've ever owned except maybe fresh razor or X-Acto blades. The wire pocket clip worried me at first, but it really doesn't feel or look as cheap as I thought it might. I really like how low it hangs, especially since I usually carry it inside my waistband instead of a pocket.

I should mention that I stopped carrying clip knives clipped onto pockets several years ago. The clips were always catching on things. Now I usually carry inside the waistband of my pants, with the clip underneath my belt. Very little of the knife is visible and it's almost impossible to snag the clip on anything. It's also been a lot easier on my pants - I was wearing out the corner of all the pockets. If I'm actively working on something where I might need my knife quickly, I just move it to the pocket then.