I'm jungling Rammus most of the time. First of all, jungle is way easier to kill in my opinion, not even near to be difficult, but get less money and less xp. I got to take my taunt lvl 3 because ganking with Rammus without taunt is kinda useless.
I tried to give more utility masteries, for better xp and more cash. it does help a little bit, but still lvl 3 after lizard and golem. It's really bad because, i know Riot will do nothing because they were proud to make that change, but it's just boring. One of the most game changing role in this game is the jungler, this guy can change a game all alone if he does his gank at the right time, but now you just got nothing good from jungling, soon nobody will jungle and it's gonna be a 2-1-2 fight all the time, when only calling mia will prevent your team from getting ganked.
As Rammus, i get 2 choices: Being super tanky mastery, but super underleveled ans with no cash. Or being about the same level as the bottom lane got a little more cash, but less tanky (wich is the role of Rammus). Maybe my opinion is only based on Rammus, i'm playing WW too in jungle and personnaly think that one of the slow jungler is even more slow because i have to spend more time in jungle.