An Olive Branch to Serge....

[softball]

Originally Posted by Winetalk.com

http://www.museum-tours.com/tours/exten_001.htm
(extensions you mentioned)
http://www.museum-tours.com/tours/odyssey_001.htm

tour itself.

The second one looks better to me. But seriously, I wouldn't do either. You don't need to. You can book tours locally. You will meet some interesting folks to travel with. Especially on the boat. And that overnight train ride to Aswan is amazing. I have not been to Alexandrian so can't comment.
You can also stay a night or two at the Windsor House if you want to experience Cairo. It was the british officers club during the war. Its old, funky, noisy,cool bar and far from luxurious but it is in a real neighbourhood with guys smoking hubbly bubblies everywhere. I love Cairo. Many don't because it is so huge and dirty. But it has history and character. Try riding the subway. That is a trip and a half.