Athearn continues to produce high quality models and the SD40M-2 is an outstanding example of a fairly popular rebuild. Units of these locomotives still run the rails today. In fact, in our own backyard here in northern Vermont, the New England Central has at least two of these units that go by us daily across the Winooski River bridge just south of Essex Junction.
The ESU Loksound couple with two SuperSonic Mini speakers provide superb sound quality and outstanding customized motor control. See and listen for yourself: