Yes – the extra carrier just drops on the tail end of it, so it must be good for 63kg anyway. That said two adult and a child shouldn’t add up to 45kg of bikes really – remember it’s 2.2lbs (not just 2lbs) to the kilo so that’s an average weight of 33lbs a bike.
In use it’s simplicity itself – though 14kg held at arms length as you attach it can feel a little heavy if you’re delicately built (I’m not, so no problems). I normally have a 2 going on 3 year old charging round me so I’ll see your 7 year old and dogs and raise you
The sliding mechanism gets a little gritty but I guess you have to expect that when it’s slung out the back of the car – doesn’t seem to affect its operation though (weekly to fortnightly since October).
Make sure you get the 13 pin European electrics on the car if you have the choice as you need that for a full set of lights – though you’re legal with the included adapter.
Overall? Simple, secure (wobble-wise), lockable (but don’t count on it being theft proof if the scrotes really want your bike), wish I’d got one years ago.