Too early to say - Lovren was good to be fair, but he wasn't tested. That said, he dealt with pretty much everything that came his way.
Gomez is still raw and easily beaten on a couple of occasions.
Clyne is the only real upgrade IMO - big fan of him.
Stoke didn't really create anything if I'm being honest and there were some nervy moments. I think the worrying thing with today's back 4 is the lack of ball players - Lovren and Skrtel are poor at playing from the back, Gomez is pretty good - Clyne was disappointing though. Was expecting more quick passing from him.
But we still need to improve IMO - get a replacement for Skrtel and put Can in front of them, then I think we have a solid unit.