Went to a train show yesterday and I picked up a CMX clean machine in HO. Wow that sucker works great. Got it for a good price $109. It's solid brass constructions makes it quite heavy. I needed to run it behind a pretty powerful engine and I got some wheel slip when it goes over a re-railer but it sure cleans the track as advertised. The springs that push the cleaning pad onto the tracks pushes down pretty hard which creates allot of drag. I was having trouble cleaning inside my 2 truss bridges as my hands do not fit in there well. With the CMX it's fun cleaning the track.