In reply to Toerag:
> It's because hexes are best thought of (and most often used as) giant nuts (which can be used as cams in some situations), whereas tricams are best thought of as cams and used as such.
That's certainly how I see mine. If I want passive gear above size 10 (Rock or Walnut) then I'll carry hexes every time. In fact I don't own large Rocks/Walnuts. Hexes are lighter than the equivalent sized Walnut, have 3 placement orientations as opposed to two, and can be slung on tape or cord, so need less extension. (Actually I find hexes on wire prone to joggling out).
I know you can place hexes as active protection, eg in parallel sided horizontal cracks, but I've hardly ever done that since the advent of Friends (so that's for the last 40 years!).
I own a few tricams, bought in Boston for use at the Gunks - they went well in the fabled "Gunks horizontals" - but I barely ever carry them in the UK. Personally I find them fiddlier to place and less re-assuring than cams, though they are, admittedly, cheaper.
Martin