This is much related to personal taste, as most of Northern people are not quite getting along with Saigon’s food flavors. What I like is a big range of food. Many choices for your eating, especially breakfast. It will be easy to stay a month but you don’t need to eat the same courses each day
Service is much better then elsewhere
No matter what service you use, small restaurant or 5 star service standard, you will feel comfortable and ‘be served’. That is hardly to get elsewhere in Vietnam, especially Hanoi.
Taxi is good
You will have reason to worry when you use Taxi in Hanoi, but in Saigon you will find more reliable taxi around. It is not only to reputable taxi operators like Mai Linh or Vinasun, I found others are also fine. They are helpful and honest on serving.
Things seem to be cheaper now
Depending on services you use, but lately I found cost of living in Saigon is cheaper than Hanoi. Accommodation is 20% cheaper than Hanoi in the same standard. House renting is even lower at least about 40% which is great chance for anyone wish to stay in Saigon at the moment.
Weather is stable
It is sunny and hot year around in South of Vietnam including Saigon. I personally don’t like sun and heat but stable temperature and lower humidity would please most of people especially Northern where the weather is always hard to predict.