Doctor Who Series 6 - Blu-ray complete series £35.00 (or £25 - £10 on HMV gift card if you are an o2 customer)
Cheapest price if you already have HMV credit and/or you want to buy on the High St. £35 is the price in-store and online, but if you have an iPhone there is the 02 moments app and you get £10 gift card when you spend £30, so buy it for £35, get £10 back, so £25 in total..
I already have quite a bit in HMV credit, so only costing £25 :) Picked up from HMV Birmingham today.
Probably ought to say is you have to be an o2 customer to use the app, but pretty sure you can be PAYG. Actually just looked on the website and you don't even need the app, just go to http://www.o2priority.co.uk/moments and login and it will text you the code back.. nice.