Yes been there looongtime ago (1999), a one-week cruise from Luxor, had a fabulous price thanks to my job in tourism at the time...
I loved it but I love history/culture... Fascinating culture. People were nice really but the political/social situation has changed a lot since. It wasn't especially safe then, I think it's quite worst now, especially for women.
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It's not as it used to be in Paris. A lot of places are opened, especially touristy. Just avoid the traditional marchs which start at place de la République. It's Workers' day in reality, not Labour day.
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There are like 18 Eurostar a day, so you can do it. But to each his own
Eurostar is like a typical fast train (well faster on the French side), it's no Orient Express.