I just bought a DSP&PRR 2018D Mogul. I guess you can say that it is my favorite since it is the 4th one I have owned. I sold the others when I transitioned to tinplate, but I should have kept one to run my Christmas trains. I'll post some pictures when I get the holiday layout up. I also really like that Mallet.
I tried to use a low cost Bachmann to to pull the Christmas box cars, but the wheels slip on the curves and it tends to stall.
George