Next cheapest is only £53.98 but this works out an incredible deal when taken into account that:
Torchwood Series 1 BD - £21.49
Torchwood Series 2 BD - £32.89
Torchwood Children of Earth BD - £14.99
21.49 + 14.99 + 32.89 = 69.37 - giving you a saving of around £18! What I would call a bargain, non?
Plus you get a lovely new case!