Twitchy games aren't ideal but still playable.The experience ain't consistent from the reviews I've seen. Some ppl ain't getting that experience on their local network.
Alot of ppl are saying fighters and first person shooters are unplayable on this thing because of the lag
I am playing Madden on this and doing just fine. But I wouldn't use Portal for Madden if it was a league franchise game.
Also whoever is playing these fighting games and shooters tell them to change the graphics mode to performance. It will help with smoothness and FPS. There's no point on playing the game in 4K graphics mode when the Portal doesn't support 4K.