I just had it done so I am a bit biased.
I had a single syringe injected into both cheeks and a bit of restylane to smooth out the furrow near the eye. I have had serious undereye circles for years (hereditary) and had undergone a recent weight loss so I looked ill and tired. The nurse who injected me was smart, conservative and gave me exactly what I needed.
There was a little bit of pressure and a twinge--she hit a nerve but beyond that it was painless. I now have a bit fuller cheek and a bit of softening of the tear trough. I know that it will never now be a dark circle but at least now people see my face first.
Definitely, gave me a few years back. We'll see how it progresses.