I have nothing but praises for this headphone:
- light, comfortable, compressable to a small size
- no connection issue or lag when connecting to android/ios
- AMAZING sound with stock pads: punchy base, clear treble. Absolute refreshing experience to relisten all of my songs
- leaks considerably less sound compared to other open back headphones ive owned like grado
- speaking of which, the bass is stronger with koss compared to grado gw100x while keeping the same amout of treble and clarity
One cons as other have mentioned: lack of multi point connection, however i have a fix for this - when you turn it on it will connect to the last paired device. So to connect to the another pair, make it into pairing mode when youre turning it on and then connect from the device that you would want to pair
All in all, affordable yet delightful sounding headphones with always on transparency mode (due to its open back nature)