That set is one I've wanted for a long time myself. One of these days...
Be prepared to tear down the engine and re-lube everything. Sometimes the grease on these older Lionel engines hardens, and it will really affect the performance. Be cautious of hardened grease in the crevices of the worm gear (on the armature). Once lubed, these modern pullmor-equipped engines run very smoothly and quietly, especially since (according to my guide) that engine has the electronic (not mechanical) e-unit. It is true, though, that they do not have much in the way of low-speed performance, if that is important to you. (It was never important to me... life's too short!)
I do not know anything about MTH transformers. I do know that many systems use "pulse power" (short bursts of higher voltage) to coax lower-than-designed speeds out of engines with can motors. Perhaps your MTH transformer is of this sort (again, I don't know). With a pullmor motor, pulse power helps the low speed performance only slightly, and makes the motor noticeably noisier. They are just plain happier on something with a pure sine wave output. Even so, I have many times run my older Lionel engines (with and without electronics) on pulse power (from Lionel's TMCC) and nothing has broken yet...
FWIW
