I forget about the Premier PRR L5 ...yet another unique MTH model that nobody else has made. With the P5A, that's 6 PRR box-cabs...and I sold them all
From memory: Unique MTH scale PRR steamers: I-10 decapod; L-1 Mikado; H10; and A5.
One PRR steamer that Lionel made and MTH didn't was the CCII.