The price and booking systems are a little strange. In the way Cairo-Aswan, I booked a second class ticket (£58) online (enr.gov.eg), paid by Visa through an Australian website! But I had to book 3 times: the first one, the Egyptian website crashed after the Visa confirmation; the second time, I got a time out (“reservation expired”); and the third time, the reservation went through and could print the resulting Pdf file in a shop in Cairo. I was charged 3 times, but get my money back for the second booking, so that I paid twice. My reserved seat (#1) was close to the door. People always going through prevented me to sleep well. In Luxor station, I simply walked to the first class and the last 3 hours were more comfortable.
My second ticket was from Aswan to Edfu, but bought the ticket in the train because the queue was too long in the ticket office in Aswan. So I had to pay my ticket in the train (£24).
The third ticket, Edfu-Luxor, was also paid in the train (£33). I can understand that I have to pay extra while in the train, but it is somehow surprising to pay almost the same for Aswan-Edfu-Luxor (3h trip in total) as Cairo-Aswan (13 hours).
Finally, to come back from Luxor to Cairo, I bought a ticket a few hours before in first class (£90). The particularity was how I got it: the ticket office told me no place was available for the whole day; but in front of it, some people were trying to sell their tickets. So with Hamdy in the midday, I took one like that, after asking the employee. The ticket was perfectly valid; I had no problem when checked in the train. The train however came 15 min late in Luxor and stayed 45 min more, waiting that the train Cairo-Luxor leave the track! Consequently, I arrived one hour late in Cairo.