i use the rival 100 and my hands are basically tiny, i palm-grip it and it's perfect and i guess claw grip would also work pretty well. some people say that the sensor is bad or whatever but i don't have a problem with it. the led turns off randomly when i lock my computer but that's not a big deal since i don't like lights anyways. the rival 300 is apparently a big larger but i don't think that would ever be a problem since the rival 100 is still on the smaller side for my tiny hands.
i've been wanting to get a zowie for some time tho but i can't one to try irl, but everyone says they're super good so try one? also what's the difference between the ec / fk?