Personally, I would avoid that doctor/procedure.
If you can afford to have FGs and travel to the US, Marten may be your best bet.
Each doctor has their own style. Some prefer to slightly overfill, some like to fill to little and 'layer'later as time goes on, others like to try to perfect it first go 'round. Some doctors are 'gimmicky' and try to give it a more marketable name, but (IMO) the really good doctors are honest and straight forward calling FGs, FGs not some other name that makes it sound like they've perfected something special that no one else does/has. Doctors like Guyuron and Marten don't have overkill websites and very few B/A pics, they are the more 'word of mouth' doctors who don't need a lot of hype and marketing to attract patients.
Most people have more than one round of FGs but a rare few can get away with one round. It's subjective and perhaps better technique with some docs than others.
As WG says, most people don't quite look the same afterwards. There's a difference in their appearance that does not always recapture their former self. That's not to say it does not look good, but most people don't look exactly as they did, whether they have had damage or they have not. The good docs ask for pictures of you when you were younger, so can imitate the fuller faces of youth and are more artistic in their approach.
FGs in different parts of the face, like fillers, can dissipate at different rates or take better in one area than another. There's little way to know beforehand if that will happen or not.
That's my two cents, for what it's worth (about one cent).
"It is a good thing to learn caution from the misfortunes of others."
"If you wish to succeed in life, make perseverance your bosom friend, experience your wise counselor, caution your elder brother, and hope your guardian genius."