I have not had good experiences with any spring-loaded or switchblade knives. In most instances, the steel was not the high-Rockwell type for a real utility knife. A friend of mine owned a German paratrooper switchblade, that made a decent screwdriver, and that's about all. Police models may be better, but may not be legal to carry.
Currently I use a Spyderco sheepsfoot knife, one-hands great (as long as you've practiced with it a time or two before trying to pull it out to cut a line when you are in a pinch), and comes in all stainless.
I'm presuming you're thinking of line-cutting duties and not knife-fighting. If you're thinking of the later, ponder for a moment why good combat steel costs so much, and debate whether or not you want to stake your life on a knife that isn't quality.