Lee, I thought about a ZW but with the now 2 MTH units that would've been the wrong move for me for lack of CV control. Trying to set any MTH CVs with a standard controller{clinks/clanks} is a really P.I.T.A.. I'll start searching around for an MTH full controller. This is somewhat expected for me...no shock the train companies want proprietary controllers for their engines...they wouldn't want you going and buying a Lionel controller for your MTH engine or backwards from that...no extra company revenue that way. Built it brand loyalty for the most part...