If Game really do have it for £30, buy it now - it's £36 on their website.
I usually buy my sons' subs online from one of the many "buyyourxboxlivecodeshere" sites. Have been as low as £24 in the past but a quick look suggests they're all charging £31.99 currently.
Missus has said she has seen it in Game for £30.00, so a disclaimer is required!
Ty for reply.