Those rear facing seats are for approx 6 to 9 year olds. They do not take car seats.
You probably don't need a camera for an 8 year old. Well, hopefully not.
My boys will be 4 yo by the time we get the car, they're on booster seats now (no longer on toddler car seats). I've sat them both on the demo seats on the beta displayed at NAIAS earlier this year and they fit well. I hope to get 4-5 years of use of these seats (hope they don't grow too fast!).
And as others have pointed out, each one of them alone = peace and quiet; sitting next to each other in the back seat = trouble. Now add to this the fact that they will be out of sight in the jump seats --> hence my request for some form of visual monotoring! (I can see you!! Give that toy back to your brother!)