I flew Egyptair and Air Memphis in May this year. Egyptair much better than expected; B777/A320 are better than A300 though. The Air Memphis flight was on an ex-USair DC9 and was an uneventful 30 min trip from Aswan to Abu Simbel and back. I've not heard of Luxorair? There is another company called Menajet who operate A320s.