I think the move is great news for everyone, except the greedy bu&&ers at TBI, the owners of BFS.
BFS has become nothing more than a shopping mall, with zig-zagging corridors forcing people through shops, and of course, with the expansion of the low cost operators, the whole Airport has become more like a Sunday market.
It's only a matter of time until BA relocate lock, stock and barrel to BHD and I am sure the runway and instrument facilities will be updated as required.
On the subject of low vis, rtemember that BHD sits at sea level where as BFS is 250ft up, at the bottom of a basin. Therefore BHD is much less affected over the winter months than BFS.