Not fit to play O'reily in OZ

Im at the 5th season of OZ now and watching Dean try to perform the character of Ryan O'reily is getting more painful by the minute.

There was a topic about this on IMDB already which stated he was a horrible actor. Now I wont go that far as I havent seen him in any other role, but I am absoluty sure that playing a badguy/criminal is just one role that is not fit for the actor that is Dean Winters.

Every line he delivers is so unrealistic, so fake that its becoming annoying to even seeing scenes with him. It's such a shame, because almost every other actor in OZ is giving Oscar worth performances..and for me (NOTE: THIS IS MY OPINION) Dean just brings the whole series down. His monotone voice, his failed "badboy" looks...I just dont understand why the writers didnt kill him off after the 2nd season. (His monologue in that season where he talks about Cyril's life is the worst piece of acting during OZ)

I mean its OZ, every episode someone gets killed. And O'reily isnt really essential to the series, on the contrary...

Like i said, I wont go as far as saying he's a horrible actor. But when you keep on struggling for so long, just not being able to perform the character after a couple of years...then it must point out that you're not that good an actor.

Please discuss and please dont give any arguments like "I dont care what you say, Dean is hot!!!! :D :D :D (L)" I really like to understand what people find good about Dean Winters portraying Ryan O'Reily.