I have played 
for most of my ranked games(which are few) or normal's and find him a good counter to many mid laners who are commonly played in low elo. The problem is i also tend to support a lot. Would Cho'Gath be a viable support with both a knock up and silence?
As with mid or top Cho'Gath, he's very skillshot-dependent: if you can't land those, you're doomed. However, he gets a ton of free stats from his ult, and his base values are fairly high. He's highly immobile, however, and lacks any defensive capabiliites.
tl;dr He's a kill lane support, like Annie or Kennen. You can snowball your lane and win the game hard, but if you get put behind early you're never coming back.
He has a knock up and a silence... Maybe
