Hello.
I'll be flying the A380 from LHR to SYD next summer (winter in Australia) and I would like to know how comfortable the Premium Economy cabin is. I'll be on 36K on both flights just in front of the emergency doors.

So, is it a good seat? How could I change it (or is it possible to change it on qantas.com)?

Then, I just wanted to know if it will be possible to visit the other cabins on the plane like on the lower deck (+ is it easy to go out from a window seat without annoying the passenger next to me)? Are there windows in the lavatories?

Sorry for the questions and I hope it hasn't been asked before.