I've been a Cho main for 3 seasons now. He's broken right now, he should not be able to be that threatening to squishies and tanks at the same time while being super tanky. It -used- to be that Cho had to choose between damage and tankiness, now he can build full tanky, letting his E shred tanky targets and his R burst squishies.
Normally juggernauts deal -less- damage to tanks the longer the game goes. Darius will shit on you in lane if you're a tanky champion, come 30 minutes however, if he's not insanely fed, he will be much much less threatening to you, so as long as you make him stand still and away from your squishies you can deal with him. Cho however right now deals -more- damage to tanky champions the longer the game goes. 10 stack Cho is one thing, but the longer the game goes the stronger his E gets, the harder he is to kill, he scales inversely through game-length unlike other juggernauts.
He's not unbeatable, but a team shouldn't have to jump through so many hoops just because I picked Cho, if we tone down the %HP damage on his E he'll probably be -fine- (and go back to being a nigh-unplayable laner in the toplane).