If you are lucky enough to have a commercial track in your town , I would go with what ever they race . you will get a lot more satisfaction running with a large group of new friends. As for me, we have no commercial track , so I run HO. Somewhat because that is what I had as a kid and also the biggest selection of cars, and I can fit a lot of track in a small space. I have a 4 X 8 , 4 lane set up right now. Some day I may add trains as well.
Russell