When he plays well, he is a good defensive centre. Played a big role in both the cup semi final and final last season. And had decent games defensively against Warrington and Cas recently. But those decent games are becoming rarer, and the sight of him on the floor after being trampled over by Tex Hoy was a pretty sad one. Looked like one of the player's dads had come on for a game.
On top of that, I don't think the pairing of him and Briscoe as a centre / wing partnership ever really worked. Most, if not all of Briscoe's tries were assisted by O'Brien, and when the play did go through Hardaker, the pass to Briscoe ended up in touch. And they never really defended kicks very well either