Until recently, I had a large Smith & Wesson S.W.A.T. folder in black w/ partially serrated blade. The blade was plenty large at 3.75" but would still pass through airport security (pre-9-11) and was street legal in most states. It opened quickly and was really rugged. The serrations would cut through rope with ease. The blade would take a good edge, but wouldn't hold it very long. (Is that because its 440C?) Best of all, it was reasonably cheap, so I'm not too down about losing it a couple of weeks ago. My biggest regret about losing it is that if was their first millenium run and was so marked, so may have had some collectors value on down the road.
I too am looking for a replacementm, and am considering either getting another SWAT or a CRKT M16. CRKT's new M18s look mighty sweet, but are out of my price range.