I pick up the road names that I like for rolling stock freight/passenger.
So all manufactures mostly evenly spread, whoever makes a roadname or car that I like I order.
Most locos are MTH on main layout love the operating system DCS.
1 Lionel, 1 K-Line, 2 Weaver on main layout locos that I really liked.
For my mostly 0-27 Kids displays that I do for public shows mostly Lionel engines and freight/passenger/operating cars as they had engines that are colorful, known and interest the public main themes; the Polar Express, Christmas, circus, Thomas, Nascar etc.
The scale more static display Brass locos passenger cars are mostly 3rd Rail, Golden Gate, Weaver.
So most all O builders are in my roster in an even spread overall.
I have to agree with this from Allan;
"My sentiments exactly! I buy based on the trains (roads and era) and have both DCS and Legacy available, as well as conventional. I couldn't care less about any "brand wars" or such. Every manufacturer, from the smallest to the largest has produced their share of winners and losers."