I have to admit that the aft torpedo tube on the 777 is not ideal. If they (or TC) had stuck with the Boeing standard crew rest, the augmenting crew could be out of the way during the busy pre-flight and pre-start time, and even for the takeoff. (I understand the standard crew rest seats are certified for use during takeoff and landing.)
However, from what the Whale crews tell me, the 777's aft torpedo tube is loooxurry compared with the poorly sound insulated play pen they've been saddled with in the middle of the Whale's Economy cabin.