If we are talking a true gaming headset (built in mic etc) then I reckon any of the top Sennheiser offerings are your best bet depending on which you prefer. Game One, Game Zero, GSP500 and GSP600. Well built, with great mics that mute on rotate, and a volume dial. Just makes things simple for gaming. I still love my GSP600 for gaming, the isolation is great when my GPU is going full jet mode with no outside distractions, imaging and directional cues are very good, and it may not be a 6XX but music still sounds pretty damn good compared with your usual gaming headsets. I see myself using the 6XX for music and the GSP600 for gaming going forward. So much easier than having a fixed mic and two or three cables hanging off my head.
If you don't need isolation then the GSP500 is probably an even better bet than my GSP600. It's open back so soundstage should be better which will probably help in competitive gaming. Considering they're R2599 on Wootware these days I reckon it will be a struggle to get a half decent audiophile headphone plus a boom pro or mod mic (especially new) for the same money and you then lose the convenience. They're all relatively easy to drive so onboard audio will suffice until a dac/headamp is used.
The older Game ONEs and Game Zeros are going for R1500 or so used these days which is also a bargain.
Just my thoughts. I reckon if you exclude Sennheisers offerings then yes most gaming headsets make you pay for all the wrong things. But, Sennheiser I trust
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