I carry a Puma 270 3.75" folder all the time. This is my "utiliy" knife for tasks that involve cutting.
I also carry a Sykes-Fairbairn second pattern. This is my "non-utility" knife.
And sometimes at night when I feel like it, a British Kukri.
Strengths/weaknesses? Is the rat-tail tang on the SF a problem? Any better knives? I don't know much about knives.