I bought this headphone to block out environmental sounds in a work environment, like people chatting, children crying, phones ringing, computer blips, etc...
There is almost no impact on these sounds when noise cancellation circuit is on. I used other products before that and they were way better for such use cases, I just forgot what brand/model, so now I ended up with this Panasonic.
Another drawback is that - since noise cancellation is useless, it still needs a charged battery to listen to music - even if noise cancellation is off.
If it were sold as a normal headphone - without noise cancellation features I would give it probably a 4.5