In HCMC, it s easy to find a housing not far from 919, many apartments around (5-10 mins), it is in the city, and 919 is close to the airport (3 mins), so you can leave your home 1h30 before the flight,even less.
In Hanoi, near 919, you can find only Vietnamese style housing, nothing for expats, no western shops, no expat school , no clinic....NOTHING !!! So you can't live there!! Unless you are Vietnamese !
The West lake (around Sheraton) is the most convenient place to live for expats, with schools and western shops...
Here in Hanoi, until now the free pick up at Sheraton was 1h50 before the flight, and now, with the trip to go to 919, wait the crew bus there , and then go to the airport, you will have to leave your home around 2h30 mins before the flight,cause you have to cross a narrow ****ty bridge always packed with motorbikes and cars, and you will need more than 1h to get back home after the flight.
So if you don't like easy life come here...
Or Dehedral1, maybe you can ask to move to Hanoi if you like it, and to compare...