I've been enjoying the heck out of my Kizer Assassin. Based on feel and action, it is the best I've experienced among the current wave of button locks. The manual action on the Kizer is much nicer than the assisted actions on the Kershaw models mentioned. The Kizer also runs
much better steel. The Radar is only running 8Cr13Mov, which is barely adequate by current budget knife standards. The Misdirect runs 4Cr13, which is radically subpar and comparatively lousy on edge retention.
BTW, Kizer has been killing it lately on the budget knives. I can second
BJE
's recommendation for the Begleiter 2. It is a different style of knife from the Assassin but also uses a button lock. Here are pictures of mine. (Note: I modified my scales a little by rounding the edges and corners. I do that on lots of knives.) For a liner lock, I've also been impressed by their full-sized Sheepsfoot Domin. The action is truly remarkable for a budget knife. All three of these run 154CM and are competitively priced.