Thanks for the detailed explanation. A couple more questions. Is the Perfect Shot front heavy? I also keep hearing how it's a tight fit for Wiimotes and it tends to shave off some of the Wiimote's plastic. Also, I keep hearing that the trigger finger becomes tired since it's a spring trigger as opposed to a soft one.
The Nyko has a layout that mimics a pistol and feels natural for light gun games. The trigger feels firm when you pull it and the perfect shot has a built in plug to re-route the nun-chuck port so the whole setup makes sense.
The Zapper is crappy attempt to throw some cheap plastic together and call it a gun. The nun-chuck is located in the back of the Zapper, which means the trigger you will be using for most games is the forward trigger. It's small for anyone other than a child, and feels terribly awkward.
The easiest way for me to explain why the Zapper is awful is this: take your hands and make two fists, line them in front of you by putting your trigger finger hand in front of the other hand by about 4 inches, now imagine holding your hands in that position to play a game. The Nyko allows you to hold the controller separate like you would with a wiimote + nun-chuck combo, it's just that you're holding a pistol shape instead of the wii-mote.
Look at some pictures, you'll be able to see what I mean.
That most likely will not be an option for me. I live in a fairly dense area so chances are clearance is cleaned out.
If you are lucky, you might be able to find some Perfect Shots on clearance. I picked up a camo one on clearance at Target a couple of weeks ago for $7.49.
Also, if anyone has tried the Nerf Switch Shot (most likely not), I'd like some opinions on that as some people are saying that one is secretly good. Plus... it shoots Nerf!