Steel is one of the LEAST important parts of a knife, unless you are using it in an application that would be excessive for one steel, but OK for another. Typically, as a steel gets "better", it worsens in another area or two, like trading edgeholding for toughness and sharpenabiity. 440A is usually seen as a garbage steel, but the right manufacturers can make it sing. 440C is often seen as much better, but from a lousy company it might as well be a sharpened soup can.
Typically, edgeholding is given as being better with one steel or another, but if one company runs S30V @ 57-58RC, and another runs it at 60RC, there will be a big difference in edgeholding and the way the knife sharpens.
Evaluate what you will use the knife for, then find the knife designed for the task, and you would probably never know the difference over which steel the knife was made of. The exception to that would be for a specialized task, like cutting cardboard boxes all week with no option to resharpen. In that case, the design would need to be spot on, and steel choice would be considerably more important.