I see. I also prefer UK railways but that's probably home bias as it's naturally the one I grew up learning about.
Is there any sort of American equivalent to Thomas, a series of stories about US locomotives? As far as I can recall there's only one American loco in the whole of The Railway Series, and he only appears in a flashback as a rude, reckless asshole who gets turned into a pumping engine as punishment. Doesn't exactly leave the best impression on a kid as to what US engines are like.