I don't have a favorite brand. I own Williams brass locomotives (4), Lionel (2), and 3rd Rail (1). All are TMCC controlled. I don't own any MTH locomotives (they are pretty, but...) because of my experiences with DCS.
I too, run scale sized locomotives, and I will buy the brand that has what I am looking for (within the limitations indicated above). For example, I am looking for another 3rd Rail PRR I1s Decapod (short tender).