I bought those headphones, as "field equipment". In cases, where I do not want to risk my prime equipment (Beyers) to be destroyed (crowdy, noisy and partially drunk environment). So...
Good things first.
They sound not bad. This is not great sounding pair of headphones, but for this price, they are not bad at all. They sound "plastic" somehow, but acceptable. You may use them for non-critical monitoring, for vocal monitoring, or - to feed your drummer with noise.
Now, the bad things.
They are noisy! The construction/plastic used, cracks by any movement. very annoying.
They are definitely not comfortable. I have big ears, but no problems with AT or BD headphones. HD-662 F are causing a lot of pain (not my favourite addition to music making).
Reassuming - good headphones on budget, but definitely not as replacement for your Beyerdynamic, Audio-Technica or Seennheiser ones.