One thing before we get started here, please keep the thread free of Nintendo hate, and trash talking them for ANY reason. I know you guys can keep a civil discussion of this accessory and hope you wont crap on this thread.
Ok, so lets get going, first off, as soon as I opened the box I was surprised at how large the CPP is! I am not talking about the added width with the circle pad, but the thickness it adds with its contoured back. it makes the 3ds substantially larger, but not cumbersome.


The next thing I noticed was how it connects to the 3ds, I was interested to find out why it requires a single AAA battery. It seems that there is no hardware connection, it uses the infrared sensor on the top of the 3ds. The next surprise came with how the 3ds fits into the CPP, it does not clip in or have any latches. It instead fits snugly with some rubber pads within the CPP, the reason for this is because the CPP is not meant to be left on permanently like I previously thought. Further evidence to support this is that the cart slot and internet switch are covered when the CPP is in place. When it is in the CPP it feels solid and does not have any play to it, but it is very easy to remove at the same time.

Here you can see the infrared sensor that communicates with the 3ds.
The CPP adds 2 additional shoulder buttons which is nice, we are afforded even more control options with this accessory. These are easy to reach, and feel more natural to use than the normal L and R buttons. Speaking about those buttons, the CPP places the console's R button out of reach, so the CPP adds a replacement that is easy to press and feels good. The L button however is a little more awkward to use, sitting flush with the CPP.



So enough about the features and aesthetics, how does it perform...
Very well for the most part! Once you get used to the extra heft it is no more uncomfortable to hold than the 3ds its self. I heard that the 2nd circle pad was more loose than the console's, but I dont feel that is the case.
Playing Resident Evil: Revelations feels great with the CPP. The controls feel instantly like a console game, using the left pad to strafe, and the right to aim and look. For the first time in an RE game you can aim and move at the same time! It worked ok without the CPP, only being able to move, but not aim, but with the add on, you have full control like it were an FPS.
The action and aim buttons have been mapped to the extra shoulder buttons, pressing zL to aim and zR to fire and interact with the environment. It all feels natural and as soon as I started playing I felt right at home, as if it were a Dual shock or Xbox 360 controller in my hands.
Should you go out and throw your hard earned $19.99 at this accessory? Hard to tell with the uncertainty of future support of the accessory. I know that MGS Snake Eater 3d will support it, and there is word that Kid Icarus will also support it. As long as developers give it as an option, it will be a worth while addition to the console. Maybe down the road Nintendo will integrate it into the console, but until then this (in my opinion) is a a solid option to get that dual stick goodness.