With whom did you book your trip?
I have had good and bad trips to Egypt.
The blue o2 group is pretty awesome
Scuba Diving Holidays, Dive-IN was OK.
Red sea diving college also seem like an okay Dive company but they have some commission guys who are a pain.
I was with the Red Sea group and the Dive IN Scuba group on the Thistlegronm a couple weeks ago and it was a good trip. Boat was rather old but the nitrox meter was functional which is a good sign and they had o2 on board. One of my tanks tasted funny so i swapped it but otherwise uneventful. A couple of the places I have been in Egypt have been frightening but this tends to be south of hurgada.
A couple of things... if your diving a boat and the tanks look old be sure to check them for water contamination (rock the tank back and forth in horizontal or turn over and vent for a second... they typically dont have a tube installed). Its pretty common on the older liveaboards and day boats. If you pay for nitrox check it... plenty of people do not.
I would advise against diving steel tanks.
You can quickly generally tell the better operations if most of the crew has some certification (more than one divemaster around, there is oxygen and a DAN cert oxygen provided on the boat, is the o2 full? etc...)
o.. and bring anti diarrhea meds
just do it... you feelbetter taking something you know than sorting something in Sharm.