I'm considering getting an OO/HO Scale version of the Harry Potter Hogwarts Express Train to go along with my Lionel one. Plan to do the same with the Polar Express too.
Questions to those who already have the Hogwarts train in their fleet - Do you have trains from both manufacturers? I know that they share the same track gauge and OO is a minor bit larger than HO, but based of my O Gauge set, I don't know what the scale size of these "carriages" are supposed to be. Not that much information on the Hornby site. I guess us O Gauger's are more likely to be concerned about car lengths because of the curve overhangs, etc. which is why the manufacturers always put in the car/train length in product descriptions. I like the more detailed appearance of the Hornby version, but am interested on how much larger the train appears compared to other equipment around it, say for example an American 85-foot passenger car.
I went thru the same thing when I ran N Scale (1:148 UK, 1:150 Japan, 1:160 USA) so I'm aware that there will be slight differences in sizes of structures, etc.