Menurut pemahaman saya, 'have an air about' bisa bermakna positif (elegan, bagus dan menarik, membanggakan) atau pun negatif (angkuh) tergantung konteks penggunaannya.
Hal yg sama terjadi pada kata 'proud.' Kata ini bisa bermakna positif (membanggakan) atau pun negatif (angkuh) tergantung konteks penggunaannya.
Dalam konteks kalimat di atas, saya menafsirkan
have an air about = terlihat elegan atau anggun dan menarik
Contoh2 kalimat berikut memperlihatkan penggunaan 'have an air about' dalam pengertian positif dan negatif.

Rujukan:
Menurut Oxford,
elegant = graceful and attractive (anggun dan menarik)

So often stars seem to *have an air about them*, *but Paul was different*. He was a real person, and *treated everyone with dignity and respect!*

They have an air about them, a real charm and charisma, and their school, like their parents, is very proud of them.

Yes you can, these dogs are intelligent and are great pets, either a trainer, or you can do it, with a little patience and love, you can do it, but you will have to research and see what you are to do........labs are very good dogs to train. *they have an air about them*, they listen...

Most people living in the Green Bay area just *have an air about them* and essentially exude *proud* Packer Fan.

http://www.trentcollege.net/press_cuttings.htm
http://www.geocities.com/SunsetStrip/Palms/4961/bugsyohio.ht...