Done CW, old First and new First with infant. CW is good in the two middle seats at the back of the CW cabin in the middle. As soon as they get to 9months+ I would do First everytime. Loads more room and 1A/1K as a couple leaves a lovely play area in the middle and between the seats (when in seat mode) for the little one to play in. Also as someone else stated, more chance of a free seat in First, so you could all have a seat (although it is technically against safety procedures to have an infant in the seat on their own - Apparently I was told - although only on one sector ).