I game on my couch but I couldn't see myself using this.
I have my keyboard on my lap and on the arm of my couch for my mouse I use a thin square piece of wood that I cut to the size of my mouse mat and glued my mouse mat to it.
This couchmaster is a good idea, but it is a bit expensive for what it is. You could make something like it easily for much less money.
NZXT Switch 810 - i5 2500k - Gigabyte Z68 UD3H - 8gb 1600mhz Mushkin Blackline - Asus DCUII TOP 7950 - Samsung F3 1tb HDD - Samsung 256gb 840 Pro SSD - Corsair H100 - Corsair HX850.