This is a clever little device that adds very little weight to the controller when attached, and since your hands don't use that area, they don't affect the ergonomics of gaming. I have a couple of slight problems with the device (which may just be a personal viewpoint):
1) I have large hands, so the small buttons are not always that easily accessible
2) It will take a while to memorise the green/orange second/third key combinations (which on a regular keyboard is like the shift key with a number key giving a different figure, only in this instance you press a colour key which corresponds to a character on a letter).
Overall, I am glad I bought it, and the price is well worth it especially as an extra headset is bundled in. Recommended.