Are Hopper Cars roughly the same size as Reefer cars?

Depends on the prototype and whether they are mounted on scale trucks at the proper height off the trucks and body height off the rail head.

Thanks for the reply. 

If this were a real train, not a toy, would these two cars be roughly the same heigh going down the track.  I like both items.  I am not complaining about that.  I am more curious about size comparison in the real world.

The real constraint on real RR cars is the weight.    The cars are built as big as they can be made to still fit clearances both sideways and height on the RR and still not exceed the weight limits dictated by the type of trucks/bearings and the roadbed structure.   

Modern hoppers are indeed very big and tall.   Older ones tended to be smaller both in length and height.    Up through WWII (late 1940s) most cars were rated at 50-55 tons (100,000 lbs).    You see many of the short 2 bay hoppers in this size range.   The reefers of that era were 40 ft cars and rated about the same.    As cars modernized 70 ton hoppers became common and then 100 ton hoppers.    I don't think reefers have increased in weight capacity as much, although the modern ones are bigger - at least 50 ft long and a little taller.   

I think height clearances are just changing in the last 10 years as double stacks become common practices.   Up until then the height clearances for bridges, tunnelsm, overpasses etc. stayed pretty much the same as when built 50-70 years ago or more.    so as trucks and roadbeds got better and hoppers served more big bulk markets, they could grow in size, while reefers were already about as tall as they could be.   

So summary, modern hoppers could well be as tall as reefers.