For gaming and Movies
HyperX cans are good... not so good with music since they all lack decent Treble.
For mixed usage " Gaming, Movies and Music" Arctis 3 are pretty solid but lack the bass you get on Clouds and the HD 681.
HD 681's are actually quite good for the price but I find the high mids/low treble to be rather... shrill and bright on some things. I also found the pads to be okayish...nothing special..kinda hurts after a long period of use. To make those shine you need to run an EQ and replace the pads but I suggest you proceed with caution on the pads many of them will really screw up the sound profile.
Brainwavz HM5
Those add more mid-bass and warm up the Treble around 5K, they also add more ambient noise bleaching, which isn't terrible since those cans don't block much noise to begin with.
EQ with
Equalizer APO and
Peace
With those pads use the
settings here with a few exceptions.
5K will be -2
124hz +.5
156hz +.5
One more suggestion on used Superlux, the weakness is the cable connector. They tend to pull out over time so I suggest opening them up and hitting the inside of the cable/frame with a little silicone.