I've got several Atlas engines. I've never had a problem with any of them.
I must say, having been in the hobby for so long, that the quality of products, from track, to rolling stock, to engines and structures has improved dramatically. Not only Atlas, which has been a leader for years, but with Kato, LifeLike, with their Proto 1000 and 2000 series, Bachman(Spectrum), Athearn(Genesis), Broadway Limited, Rivarossi, and the many other manufacturers and distributors making great leaps in quality and detail. Some of the "oldtimers" know what I am talking about here.
I'm glad to be around to witness the improvements.
Bob