Man, that's a hard question.
I guess for pure utility I would pick zytel or aluminum. Micarta is even better (and better looking) but it costs more.
For old-fashion nostalgic appeal I like stabilized wood on larger knives and yellow delrin on pocket-knives.
For beauty (but not strength) I love mother-of-pearl.
For some reason I never have cared for stag or bone.
I guess for pure utility I would pick zytel or aluminum. Micarta is even better (and better looking) but it costs more.
For old-fashion nostalgic appeal I like stabilized wood on larger knives and yellow delrin on pocket-knives.
For beauty (but not strength) I love mother-of-pearl.
For some reason I never have cared for stag or bone.