I'm not sure about the current HO scale cars, I see there are quite a few players in the market now selling cars that are "compatible" with AFX, Aurora, etc... But if they are true HO they will be what 1/87 scale if I recall correctly. That would be quite a bit smaller than Hot Wheels which are 1/64.
Maybe I'm just mis-remembering the old AFX cars, but I thought they were "about" Hot Wheels/Matchbox size in scale.
In the UK at least we used to have Semi's with trailers in the Aurora sets, I know that for a fact as I had a set that came with one
Maybe I'm just mis-remembering the old AFX cars, but I thought they were "about" Hot Wheels/Matchbox size in scale.
In the UK at least we used to have Semi's with trailers in the Aurora sets, I know that for a fact as I had a set that came with one
Happily collecting things all my life... 
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