In this case seatguru is fairly accurate (nothing outstanding). Rows 11-13 are generally reserved for Qantas platinum status so might lead to a quieter cabin and better service. The main section is huge. If rows 11-13 are all gone, take your pick. If I understand correctly, the WCs at the rear of the cabin are shared with premium economy, so perhaps best to avoid seats in that area.

The seats in QF's 747s and A380s are getting old now. They are not supported at the foot end by an ottoman, so over time some seats have developed a droop and not provide a full flat sleeping surface.