I received responses from the following operators and am interested in getting some advice. I will be alone so my main criteria are mostly cost, reliability, and having decent food.
Ramses Tours: $435
Desert Safari Egypte: $372
Select Egypt: $280
The services all seem pretty similar (stopping in Bahariya, night in White Desert, seeing Black Desert en route), so it's hard to differentiate based on that. All else equal would of course go with Select Egypt cause of the price, but interested in any feedback!