I can't say that I one have particular knife that I can't live without. But I did run into the same problem you have. One knife that I couldn't get out of my pocket. No other knife was better for me. I actually sold off almost my entire collection because of this problem. I sold all my kershaws including my S60V blur!, old school benchmades, my new fancy benchmades, my Camillus Cuda Maxx, my Fox Col Moschin, Military's, Para Military II, Hogue Ex01's etc etc
The knife I am talking about is my Cold Steel American Lawman. I did finally end up carrying a Hold Out II for about a week, it's nice, it has a nice thin blade, but is too small over all. Right now I am carrying my newest knife, a Benchmade Nitrious Stryker in D2. We will see how long this knife lasts, but for now it's doing a good job. Someone before be beadblasted the blade, so it was DULL when I got it. I spent about an hour with a DMT X-Coarse stone and didn't get an edge on it (it was DULL, no bevel to speak of), so I actually sent it back to Benchmade and they fixed it right up. But now I'm actually getting some rust on the blade. (it's been pretty sweaty here lately)
The edge is not terribly fine, but after about a week of use I can just strop it and it's back at shaving sharp.
Anyway, that's my morning ramble.