These headphones are really nice - but the included software is awful. Out of the box using the Steelseries software, they sound really weak and have almost no bass. I don't mean this in a 'neutral' or 'flat' sense. I have proper hifi headphones which are quite flat, but still have bass. These things just have super weak, muddy bass, coupled with indistinct mids.
The problem is not the hardware, but the software. Installing a free, open source equaliser (Equalizer APO, available from Sourceforce) transforms these into a really good headphones.
Another thing to note is that the advertised 7.1 sound is garbage. The headphones are pure stereo. All that you get is a really bad implementation of the DTS virtual surround standard, again through the awful Steelseries software. Windows 10 provides better (but still poor) virtualisation built in, but overall I wouldn't buy these expecting amazing directional sound. Another issue is that even with the Steelseries software installed, the headphones will not appear to Windows as a 7.1 capable device, which is the main way most games will decide what sound signal to produce.
The wireless works really well and the physical headphones are very comfortable but satisfyingly solid.
So overall - buy these if you're happy to mess around with software to improve the sound. Don't but them if you want great sound out of the box or if you really need good directional/surround sound features.