I believe that Stern is better than Zamora. Even Kenwayne with a little more experience is better than this guy. If you watch the EPL you'll realize that they place a value on horses(big strong athletes). That is why Harewood is successful and shitsnake Heskey getting a sweat. None of these guys are international quality or good on the ball. Stern get less sweat than these guys and score more goals for Birmingham. He was their leading scorer and they still get rid of him. Clearly he is a better goal scorer than these guys. Now they'll get relegated for chasing those shithounds.
Also, it is tougher as a forward to succeed in the championship than it is in the EPL. The championship game is based on toughness, fitness and grit, that is why Zamora did well there and Stern is struggling. In the EPL forwards are better provided with opportunities by their midfielders. The SPL is the same shit as the championship except for the old firm. Stern better off in the MLS or French league, anywhere where the physical requirements are not as stringent.
Having said all that, he still needs to get fitter and increase his workrate some.