You didn't mention how many kids you have, but here goes my thoughts:
I've never cared for bunk houses. Some of them are quite short. Short enough that growing boys will outgrow in just a few years. I also don't like the fact that a bunkhouse is usable for pretty much one thing - sleeping. It isn't a multi use area.
Rear living puts the kids on the dinette and couch, that is true. Or, if you find the right rear living plan, they can have a full size bed fold out of the couch. That is the way our current TT is. It literally takes about as much time to fold the couch out as it does to do a jacknife couch. Each kid grabs a sleeping bad, throws it on the folded out bed, and is ready for sleep in just a few minutes. 15/13, 6' tall and 5'7" tall. Working like a champ.
Space in a camper is limited, and I really like to have multi use spaces.
Now, if you have more than two kids, things change a bit. :-)
