On myt last trip to Egypt last summer i went scuaba diving in two wonderful places. If you are looking for a great and cheap scuba wonder, Egypt is the place to go (Once the whole conflict gets better).One of the my favorite places for scuba diving in Egypt is Sharm El-Sheikh and Dahab. I did my advanced open water in Dahab last year as well and it was awesome, great little town and the only place in Egypt I have any interest in returning besides Sharm El-Sheikh.
Amazing waters, however the people there were not so great. Pretty much everyone is only interested in getting money from you. This includes the Tourist Police. If anyone tries to "give" you something, don't take it, because they'll want something in exchange (don't have anything? Money will do then). Don't take up anyone's offer of taking your photo/having your photo taken with them, unless you're prepared to pay them. If anyone wants to show you anything - a tourist attraction, their shop, whatever, "for their pleasure", they want you to buy something or pay them. If pretty much anyone says anything to you on the street, they most likely want your money. You don't have to completely ignore them, but don't stop walking either.
I don't know how bad El-Sheikh is, but I got hounded by these people literally everywhere I went in Egypt. Although other travellers I met hadn't had any trouble at all. They usually don't want much, mind, but when you get it several times a day every day for weeks on end you do run out of patience. But don't be too stingy, remember, alot of these people make like 2 dollars a day.
Also, don't use taxis which don't have meters in them. Even if you agree a price before getting in, it'll change. If you do want to buy anything and the price isn't marked, haggle - you shouldn't be paying more than 25-50% of what they claim the price is. Just act indecisive and go to leave, the price drops instantly.
If you want to try Shisha, go visit Omar: Master of Shisha in Dahab. Best shisha in the world bar none. Any pipe you get given in a touristy area in a bar/restaurant will be horrible. Speaking of restaurants, many are BYOB in Egypt, even those that serve alcohol, and it's half the price in the shops.
All in all Egypt is so freaking great, lots to see one of the best scuba spots I have ever seen however you just have to know how to work your way around the people trying to take your money. I grantee you, that you will leave Egypt a little more streetwise.