Wife and I watched the first season. Very depressing, no redeeming characters in the show, lots of violence, and seemingly no hope for any improvement. Started season two and gave up due to more of the same. Just a huge downer to watch, kind of like the last couple of seasons of Sons of Anarchy. That was our opinion.
As noted above it's dark and gritty and at times it got a bit too over the top for me but overall I enjoyed it. It's an interesting plot that's different so that has a bit of the draw. That and Jeremy Renner is really good.
Just been too busy to get to around to watching S2 yet.