Thanks Nick and Nathan for your help.

Yes, I understand, but I was told by a knowledgeable dealer, that his customers were changing the decoders to MTS, and I was wondering why.  Thanks for your help.

This question is for the Bach-mann, or anyone else who has an answer.  My G scale layout is controlled by LGB's MTS system.  If I purchase a Bachmann 55 Ton 3-Truck Shay with decoder and sound installed, will I have to replace the decoders with LGB's MTS decoders, or will it run on my layout straight out of the box? Thank, Tom.