I use my He 400 for gaming, and I really like it, before I was using some sennheiser 595, being lighter the comfort was better but
I still prefer the Hifiman anyway : better sound, bass
For the price you can get the HE 400 it's really hard to beat
200 $ is an awesome price, get it and enjoy !!!
It's right the Hifiman is leaking sound and you hear what's happening around you but for the rest it's so perfect