I can only advise on what I carry every day.
COLDSTEEL.
I carry a Coldsteel brand 4" serrated Tanto pointed Voyager. It is extremely sharp and has a very strong locking mechanism. The clip is steel and holds the knife tight on whatever its clipped too. It has ambi thumb studs for ease of getting the blade out.
IF I am not carrying the above, I carry the 4" clip point, plain blade Voyager.
A very important point to keeping a knife sharp is a sharpening system. A few years ago I purchased the Spyderco brand traingular ceramic sharpening system for 40 bucks. It will sharpen both regular and serrated blades.
It sells now for 75 and to me is worth its weight in gold. I strongly suggest that when you do use this sharpener, that you use the guards and maybe wear a leather glove (I do) on the support hand holding the sharpener. It will make your blade extremely sharp is just a few minutes use.
Coldsteel will send you a free video of their products called "Proof".
You might get a good deal on the above products at
www.botac.comhttp://www.coldsteel.com/folding-knives-voyager-series.htmlhttp://www.spyderco.com/catalog/details.php?product=77