Comment by xattt
The Canadian export versions of the Lada full-size sedans had doors reinforced with beams for increased safety. So structurally, they were indeed built a little better.
There were several other features like western carburetors and emissions controls, but these were likely be a “temporary” improvement for the domestic market as those parts wear out and would likely be replaced with local parts.
The thing about JDMs is they tend to be more desirable than export versions, because of whatever quirkiness that gets left behind at the time of export.
There's no such thing as a Lada full-size sedan. The longest one was something like 4.15m long. Contemporary American "mid-size sedans" were over 5 meters long and even "compact sedans" were quite a bit bigger.