At first I was somewhat dubious about them creating 2 studios with an identical format, but having now seen all the programmes I am impressed.
Apart from people like "us" who know that all these programmes are coming from either
N6 or TC7, the general viewing public probably can't tell. TC7 is quite creatively re-dressed (especially for the PS and SundayAM).
(edited)
The investment in creating these 2 sets was undoubtedly large, but this will soon be off-set by the savings in not having to constantly dress and strike entire sets numerous times a day. They can also be changed to reflect a new image/format for a programme at minimal cost in the future.
I'm sure N6 and TC7 will serve their purpose well up until the move to Broadcasting House in 2009/2010.