I have a Bachmann 4-6-0 with sound and had to add weight to the tender to keep it running. I have the weight sitting on top of the tender right now as I haven't gotten around to finding room inside for it. I also noticed that the front truck on the tender doesn't sit completely on the track without the weight. It runs great and doesn't stall or hesitate through my turnouts (most have powered frog). I also have several 2-8-0's (Bachmann) and they are all trouble free smooth running locos. I find the biggest issue with the Bachmann steamers is the weight of the tender. For the price and detail, they are hard to beat.
-Bob
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