the sonesta beach club is coming up... you say this is the sister hotel is it next door/nearby?to sonesta beach resort?
Lyn is indeed correct, I have stayed there, and we dived with Emporer divers. (and no Lyn, I was not on the voddy last night..haven't touched a drop for a couple of weeks now..
).
Sonesta beach club will be fine for what you need..dive schools along that road into Naama Bay are 10 a penny and all will promise you the earth as they want your business. Michelle is the Sonesta Beach Queen and can tell you positively everything about the place....
The hotel is about 10 minutes away from the floating jetty which is where most of the day boats leave from (now that is an experience in itself!) but most dive schools will offer transport to and from the hotel FOC..and to save you carting your dive gear back and forth, they will also store it securely at thier premises ( depends how much diving you are doing and how often).
Oonas is attached to SBR and offers a very good service. What level of diver are you? The day boat run can be chaotic and sometimes quite stressful..and to be honest, unless you are going a fair way from Sharm and diving in places like Ras Mo where there are some very good reefs, there is not much life to see around the Sharm/Naama coast. Much of the coral is dead/colourless and most of the wildlife has more sense than to visit there!
Some other schools are Camel ( very highly rated)
http://www.cameldive.com/about/camel-hotel%20-
Red Sea diving college also has a good reputation, but I have not used them at NB
http://www.redseacollege.com/
and ocean College - i know nothing about this club.
http://www.ocean-college.com/
Try Emporer or Oonas first off though..Emporer have thier own fleet..
http://www.emperordivers.com
Enjoy.