Remember how that totally objective quick look on House of the Dead Overkill sucked so much? Remember how they lamented about the lack and impossibility of lightgun-y controls? Well.
(My aim isn't too hot there because I was filming, and sometimes I try to shoot when there's a non-interactive sequence)
I wonder if they bothered to use the calibration tools and the option to turn off the crosshair? You know, the option that was even present in HotD 2+3 Returns? With the proper calibration, you aim at the head, shoot, hit. You aim at the little green SloMo-Thingys, shoot, hit. All without crosshair. But with noise and rumble coming from the Wiimote. And with the Hand cannon, it's just absolutely awesome.
I played a lot of lightgun-shooters in arcades and on the PSX. HotD: Overkill is not really different. The calibration is a hassle, but once you got that done, Overkill with the handcannon is a blast.
That hand cannon thing is pretty heavy, by the way. The made the handle heavier, so it works as counterweight.