They are good running little loco's. As is, they pull maybe 6-8 cars on level, grades are a different story. You can get a traction tire from the Pacific and make it pull quite well. Also replace the tender trucks with trucks from Kato or Bachmann with all wheel pickup and you have a champ.
BLW is dumping them because MP has a new batch coming for Xmas, all with traction tires installed and some improvements, but they won't say just what the improvements are.