I like Shen, but I've had too many games where I did MAGICAL, like with sparkles flying off me that's how good I was, and I still lost. Serious 10/3/20 games where I stomped top and saved so many players with my ult from 6 and onwards. Perfect engages with (flash)taunt on AD or AP carry, or even both, and then your team DOES NOTHING. Then you try to stick to your 1 decent player, but still not enough. Frustrated me so bad I stopped playing Shen top.
As for fighting him, I had the easiest time as a Jax. Stomped his ass. If you can outpoke and sustain early on you should keep your advantage. Try to take a champion that can interrupt his ultimate if you want him to be useless >6 as well.