I have had the GL600's now for a couple of weeks. They have basic construction but are lacking in appearance unless you are looking old school type look. Head band is quite unlikely to break, it is made from spring steel. The screws will require occasional tightening that hold the earcups to the headband & that screw is likely the weak point especially if not kept tight. Another weak spot is the 2.5mm jack in the earcups, the ground terminal in one of the earcups didn't make good contact with ground terminal on 2.5mm plug causing intermittent cutouts in sound. I was able to make a tool to fix it so it no longer cuts out on me. About sound, the sound stock left a lot to be desired. Male voices were either too bassy sounding & not understandable as a result or were too coarse & shouty. Female voices were just plain shouty. High frequencies were soft & sometimes hard to hear when the whole band was playing hard. The end result was things sounded distorted to me, even at relatively low volume, much lower than I could tolerate on other headphones. Removing foam from back made things worse so I concluded they needed more damping, not less as I see some people doing so I added some more damping & arrived a more than acceptable sound. In fact they sound incredable. I did loose some sensitivity but that's only a minor trade off. They will no longer be loud enough on normal smartphones but they work great on my LG V60 which has a beefier amp than most smartphones. I can tolerate much higher volume now than I could stock & not have it sound distorted, in fact it is very clean sounding. Sound stage is incredible both in depth & width with great imaging throughout. The base driver these headphones are incredible. I wish the manufacturer spent more time in tuning as I have done. If you want to spend time modifying these they are great but not out of the box. I consider these a great buy only for those that have some idea hot to tune the sound on these. Anyone else I would say avoid these as stock sound is not great. It's pretty poor in fact.

Stopped reading at 'stockcable is really slow. Ordered a fast 6n occ cable with 16 silver plated Coppercores'.

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