I like it a lot, but I better hide this post from the misses, we have a baby due in May and I have been telling her that a Defender is no place for a baby.
On a serious note the back of the seat is a great solution I think, that said not sure what holds it the back of the seats seem quite flimsy, alternatively I have the third row seats removed and was just going to use the seat belt anchor point bolt hole to mount the seat anchor and use an extension to the child seat strap. That sounded more complicated than it should have. But if the load restraint holes are strong enough then that could be another option.
More alternatives to the big bar in the back is good I think.
Pat

