HyperX Cloud II are solid headphones, no doubt about it... but they are getting quite old now and there are many company's that have better products at the same price point. Take the Corsair HS70, or the HpyerX Cloud revolver (which is a bit more, but a much better product).
The Cloud II are winning in the vote, but when MD gets around to getting them as a drop they will be discontinued since they are getting up in age. The only reason HyperX keeps making them and has 2 headphone at the same price point when one is better; is people keep buying them lol.
Sennheiser Game One's (Open Back) with the Sennheiser GSX 1000 or another amp/dac combo would be the ultimate choice. It will give you phenomenal audio quality as well as help with pinpointing where enemies are in FPS games. It will also have much more true audio than most other "gaming" headsets. I own a pair of Astro A40s, 2 pairs of Astro A50s, and I have purchased/returned almost every product on this list. I love my Astros for the comfortability, but when it comes to audio quality, and competitive gameplay, I will always switch to my Sennheisers.
If Sennheiser Game One's are a little over budget for some, you can essentially get a Sennheiser headset (Can't remember the model) and ModMic 4.0 instead for similar quality.
I'm not saying any of the other headsets were bad, because they weren't at all. They just didn't sit as comfortably on my head as I would like. I probably also have a headset on longer than the average person so it may not be as big of a deal to most.
I own a pair of the HyperX Cloud 2's. They are very solid headphones, but personally I wish there was a way to control the audio levels; I'd love a little more bass. I'm looking into ASUS' ROG Strix Wireles; they seem like everything I'm looking for in a headset.