I value the audible feedback heard when a blade locks into place. It instills confidence that a knife is ready to use and has a strong and safe lockup. Some knives I've handled have a weak sounding lockup. Even though it may be perfectly safe, I'm left with some doubt.
Beyond that, for me, the speed and kick are just for show and don't effect the performance of the intend purpose of a knife...to cut. The importance of a Knife's action is often overrated, unless it is to be used as a fidget toy.