I use the the wiimote, never used anything else so i cant compare.
My wiimote has an ergonomic clear rubber shell so is nice and comfy.
I actually find the controls really intuitive and more important for a FPS very accurate, i usually rest on a pillow or the arm of the chair to steady my hands.
Like others i've found turning quickly ingame can be too slow but im very slowly turning the sensitivity up as i progress.
Im at the stage now where i only need slight wrist movements to aim.
tip: looking down when turning around seems to make it quicker for me, try it.