Following is just my opinion, so take it for what it's worth:
To answer you question, I'd say Buck.
I left the most stable job I'd ever had two years ago to be a stay-at-home dad. My employer (we sold high-end European hardware) had not had lay-offs for decades. They just laid off my entire sales crew at the end of April; no one saw that coming.
My dad & I had a conversation a few weeks ago, along these same lines. He was a graphic artist for years, and we talked about how a company will look stable, introducing new & trendy & innovative products, then lock the employees out one day and go bankrupt.
So your question is a tough one to answer. In both Schrade's and Camillus' situation, I don't think either of them needed to close. I've got the 2004 Sporting Knives book, and it covered Schrade's 100th anniversary. They seemed to be doing VERY well at the time. They were making some pretty standard product lines when they closed, but the quality was still there, from what I can tell. Why close? Who knows? Camillus management is the reason for Camillus closing, plain and simple. The facility needed capital improvements, (ie: apparently they didn't even have a loading dock) among other issues; things that, in my opinion, could have been solved if the right people had been in management. I wasn't there, but from what I've heard, Camillus' owners (and some management) "took the money and ran", leaving the employees & everyone else hanging.
So, in a nutshell, for a privately owned company, you never know what might happen from one year to the next. I don't think Case, Buck, Busse, Spyderco, R.A.T., etc. are going anywhere anytime soon, but who's to say what will happen six months from now.
Case, to me, seems to be a almost "desperate" (right word?) these days - it seems that they're introducing dozens of new patterns every year, but I pull my hair out sometimes just trying to get a good user with CV blades. It seems EVERYTHING they make is for collectors. (Again, that's just my opinion. I love Case knives and buy several a year, to give as gifts & support them.) Buck has a rather large presence here in the forums, and great products as well. Seeing some of their folks post here occasionally really makes me feel good about where they're at. I buy several Bucks a year as well, usually from their American made lines. Busse? Jerry's a true, honest gentleman, and he posts here as well. With Busse, I don't think they'll hide anything. Spyderco is brilliant - Sal is very attentive to what forum folk have to say about their products. R.A.T. has a large following here too . . . the list could go on & on.
However, as much as we love our "favorites", the reality is that great product lines, slick advertising campaigns, clever slogans . . . however a company presents itself, none of that adds up to stability or profitability or longevity; what we see is the best face they want us to see.
Sorry if I sound 'preachy'; I've had this same kind of conversation a lot recently with friends here who are shocked to find out that their favorite knife mfr. is gone.
thx - cpr