It might be an idea to try and decide on form factor. Kato Hammer despite being chunky ends up looking small if you keep it in your mitt rather than toking like a pipe. Button location also a decider for me. Bottom button (never got on with them), even the ones that have a low side button, they looked clumsy to me, worked ok though. Mid to upper button was was my weapon of choice, it was why the Dingo turned out to be one of my better choices. You also need to consider battery choices. 18350 makes for some nice small options, while larger batteries can take you to doctor whos sonic screwdriver and beyond.
so for me, hammer and dingo.