If you own Monster Hunter 3 Ultimate or Resident Evil Revelations chances are you probably already own this, if you're looking to get one of these for those games than it's a pretty good deal, but if you're wanting to get it for more games I highly suggest you do some research before purchasing.
The device feels surprisingly comfortable despite the extra bulk it adds to the system, I never felt my hands getting cramped nor did I have no troubles pressing the shoulder buttons or any buttons while playing, the circle pad feels more 'light' compared to the circle pad on the actual device.
Sadly, despite the device's comfort, the amount of games this accessory works for is very limited, the total number being eleven games, ten when you consider that one of the games only has support for the circle pad in it's Japanese version only.
The fact that the device also requires it's own AAA battery which has to be replaced is quite stupid, I'm a little confused why Nintendo didn't give the device a chargeable battery or just designed it so it ran on the battery of the 3DS.
It does what it's meant to, but I really don't see a reason for getting one, especially with the New 3DS/3DS XL models on the way. If you really need that extra camera control for Resident Evil Revelations and Monster Hunter 3 Ultimate then this is a okay purchase, but if you're looking for something more out of it, I'd consider passing.