Do your outbound flight in First so you can use the CCR at T5, experience the service onboard without thinking that maybe it is time to go to sleep. You can dine together on the outbound, relax and enjoy the experience.
The return sector do in Club World as all you are going to want to do is have something to eat, maybe watch a film and go to sleep. Would be a waste to do F on the return when the CW seat is quite good for sleeping...
That would be my way of doing it... ^