This seems the best deal available at the moment for an Xbox 360 premium console with the best games available from any bundle i've currently seen.
HMV are now selling the Pro evo 6 bundle with Xbox 360 premium for £279.99 and for an additional £10, they'll also include arugably the best game of all time Gears of War and the new Crackdown game (which includes a Halo 3 multiplayer game).
If you also use the £5 voucher for orders over £35, and go through Quidco, you'll receive the package for just £279.29 including free delivery.
Alternatively the same deal is also available instore but you obviously won't be able to benefit from the voucher and Quidco but you'll receive it immediately for £289.99, rather than waiting for slow delivery.
The additional tip is, if there is a Game store within a pretty close distance like there is to me (i think they allow upto 2 mile radius) then they'll pricematch the deal and then you'll receive 2.5% in reward points (£7.25) making the whole package cost £282.74 as well as being legable for any of the "When Bought With" deals (WBW).
Hope this helps anyone looking to buy an xbox 360 premium.