Saw the Bronco T26E4 Super Pershing at the LHS today. It looks good. Had to chuckle at the box are - the crew is loading 1 piece rounds, but the gun took two part rounds like the German 12.8 cm.
Also, the additional armor created a noticable "nose down" attitude that the Bronco model does not look to have. Not sure you could add it, either, given the linkage between the idler and the first road wheel. Should be doable with the Tamiya M26 kit, but I don't know off hand if the hull details are correct (mostly wrt hull ventilators).