Thoughts on Namor??

I was watching a Penguinz0 stream and it blew me away how many people were hating on Namor in the livechat. I don't really pay attention to specific heroes and I've also yet to play Namor because I don't really get what his abilities do, but playing against a Namor main can be total ass if he knows where to place himself and his turrents.

This is just a personal experience though, what do y'all think about him?