I have an issue with the boot seats in some of these cars... I'm pretty sure I wouldn't want my children to be in the crumple zone...
Pretty sure that modern 7 seaters are designed so that it is not a crumple zone to be fair.
Still, first folks to get slammed by a late breaking truck or whatever, so I kinda see where you are coming from. But the same as sitting at the back of a bus / minibus etc...
Pretty sure sitting in the back seats of a Disco or Q7 wont feel too unsafe though. Although would still prefer the dogs back there than the kids. Hence the suggestion of the 4 seats across the middle row, thus leaving the OP with the same boot space he is used to.