I've recently run into trouble (I feel at least) when jungling with say Amumu (mostly) and Shen/Rammus.
Namely, as a jungler I feel obliged to set wards quite diligently.
As a tank, I feel obliged to get as 'tanky' as possible.
The two seem to clash with each other, especially when games go bad in solo queue.
You lose a few towers early, and you desperately need to ward up your jungle/dragon, but it eats into your item builds pretty badly.
What I find usually happens is it either snowballs in one direction. If you can't convince your team to buy wards, you get eaten in the jungle. If you buy them, you initiate on the team, and they melt you.
So I guess my question is, at what point do you say enough is enough and stop buying wards?
It has me strongly favouring non-tank junglers at the moment, or just choosing to lane, because unless your team does exceptionally well, the game is always a struggle.