I don't like slipjoints because of their "lack" of a lock, and I like being able to open one handed. The clip has become less of an issue, as I try to be as discreet as possible, but its a perk. I go for knives that combine style and function, but function always comes first. And my AO SOG Blink and my Kershaw do everything I need to, they look classy IMO, and they open one handed. I see no reason to carry a knife that can't do these things just for the sake of tradition.
I used to value the earlier mentioned Kershaw for being easy at hand with the clip and for the fast opening. After I came back to enjoying slipjoints and using proper techniques instead of trusting a lock, the Kershaw got relegated to dirty jobs I didn't want to mess up my nice pocket knives with, such as cutting hose and tape while working on the car or scraping an old gasket off. When I tried to carry the Kershaw again after only carrying slipjoints for a while the Kershaw suddenly seemed bulky clipped in my pocket. I really noticed it and it was uncomfortable to me now. I will give the Kershaw kudos though. When I was working in pro camera store for a while it got a frequent workout opening boxes as stock came in and was unboxed. It was fast out and to work. Then again, a little thought or a second or two more and I would have been just fine.
Using slipjoints reminded me that knives are for cutting. Not for digging, prying, or trying to pierce auto bodies. As such, and making sure I used a knife properly kept me from poor using habits that are easily picked up with the false sense of security on a locker. I was suddenly back to actually using a cutting instrument and putting a little thought in using it. If I just absolutely need something that I don't have to worry about folding on me, then I use a fixed blade.
I carry slipjoints because I've found they generally cut extremely well, carry quite well, and that they do the job for me much better than my big, thick bladed, assisted opener. And they do it while looking and feeling quite nice. I take real pleasure just from handling and using them. I've found much more advantage to them than disadvantage. I guess you could say I see no need to carry a one handed, lock bladed knife just because they have those things on them.
As noted in my previous post, when I do feel like carrying a one-handed, lock-blade, I carry one of this in nice Bonestag.
A tad slower opening than my assisted opening Kershaw, but it carries in the pocket sooo much better, is nice to look at and fondle. And, that thin blade is QUITE sharp and slices through materials fast and furious. Faster than my Kershaw and it was shaving sharp.
To be honest, I have a Queen liner lock, single blade tear drop jack in Bird's Eye Maple that I finally thinned the D2 blade down enough on to get a nice edge on. It is very pocket friendly, but I'm so used to using non-locking slippies (real men call em whatever they want and don't care what anyone else thinks

) that when I've opened the thing I usually cuss it because I tried to close it against my leg and forgot that it had that stupid lock I have to release to close it. Maybe someday I'll send it to Muskrat Man or Oupa for a rehandle and have that liner lock removed at the same time.