Andre, you are certainly correct about the lack of 'heft'. I read a piece some years ago that gave a great explanation of this phenomena with our trains. Although HO is indeed 'Half-O' in size as it pertains to length and width and height, the three dimensions equate to the 'volume' being a function of 1/2 cubed - i.e., HO is actually 1/8th the volume of O gauge which is why the lack of 'heft'.
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