Benchmade is the only thing I'll carry anymore. It comes down to the quality and feel for me. I've got CRKT, Gerber, Spyderco, SOG and a few others I don't remember. These "other" knives are now sharp and located where I can get one if I need a knife, but I don't carry them or use them daily.
Benchmade's quality and ergonomics is superior to the other brands listed above IMO. I don't recommend anything they make with 440 steel though. I've found that 440 doesn't hold an edge as long as I like and it is more difficult to sharpen than other blade steels. BM says that is true of the cheaper 440's like 440A or 440B. I'm not conviced as I have a Griptillian with 440C.
My personal favorite is the Osborne 940 series. Lightweight, aluminum scales, small seratted portion of the blade.
On the auto thing, I don't see a reason to spend the money. Most manual openers can be adjusted so they snap open with a flick of the wrist, or practise a little with the stud/hole/flipper and you can open a manual almost as fast as an auto.