I'm not a big fan of headsets as a concept, but EPOS (formerly Sennheiser Gaming) are one brand I'm generally willing to give a bit of extra leeway to. I was also looking for a wireless headset, and I had a series of discounts which made this a bit more affordable. I've used it for over a month now, so review time.
Comfort: Pretty good. ~300g headset, good seal, and good clamping force. The volume control is on the right hand side and is a nice addition and easy to use. Feels fine after very extended gaming sessions. Not well suited for use when lying on a pillow - same issue as the Sony WH-1000XM_'s.
Sound Quality: Overall it's good (for a headset). Has built-in ANC which is unusual for a gaming headset, but nice to have. Extra points if you want to use this headset in an office! When on Bluetooth it's using SBC which is the most universal bluetooth codec - with quite low latency (it's a very simple codec) but also pretty low quality, but does sound noticeably better when on a wired USB connection (appears as a sound device on your OS). I never tried it on a 3.5mm connection (which needs the battery on!) but it should be very similar to the USB version. Overall the mids seem quite muddied and the treble feels a bit recessed. The bass seems very recessed. EQ'ing on source fixes some of this, but it remains below average (for a pair of music headphones). For gaming and film it's fine unless you're expecting heavy explosions, in which case the lack of bass might annoy you a bit.
Mic Quality: It's audibly a headset - so perfect for general gaming, Discord, etc; but not good enough if you're wanting to stream or create content. Similar in build/quality to the existing Sennheiser mic tech for the PC range and the Game Zero/One headsets. The device has two mics on it, one is detachable and one is embedded.
Wireless: Range is great, able to listen to it all over my apartment (max is ~6m away through 2 walls). I have my dongle connected to my normal mic's stand for extra height. It's a low latency device, however I will say that there is a not-so-aggressive attack on audio being transmitted - meaning that if you go from a period of no audio to one where there is audio, then you'll notice a missing first word. This isn't more than an annoyance when gaming, and the only time I found it annoying was during some films where there are long (~30 seconds), silent montages before some audio is spoken.
Other: The battery is okay on the device, I get a full day (12-13 hours) off a single charge (takes < 1 hour?) - and you can use it as you charge it. Pairing is quite easy, and the pairing device is always visible (even when the headset is off) so you don't get annoyed like when some DACs disappear/reappear every time you turn them on. The headset is quite aggressive at going into power-saving mode - after a few minutes it sleeps and won't wake-on-audio, you need to prod it. Note that my claimed use is much less than the specs claim for expected battery.
I didn't use/test the software much beyond the basics: 7.1 vs 2.0 is some general maths funkery to make it seem like a bigger soundstage and more directional. Works fine but 2.0 is fine. There is some simple graphic EQ for various presets (esports / movie / music / custom), but these are just badly implemented in general so I avoid them.
Device works fine on Linux.