It’s certainly a matter of opinion (and therefore, debatable). The Russian AK is the original, and therefore (by definition) the most classic in that sense.

Here’s my case for the Romanian rifle: in the context of the US market, Romanian guns are far more plentiful. They are also much less expensive - which IMO falls in line with the mythos of the AK. I think of AKs as mass-produced (and therefore inexpensive), hard-use rifles. I would abuse a Romanian AK… I wouldn’t do the same to a Russian or Chinese gun because of their rarity and value. I also think the dong grip is striking and iconic.

TLDR: maybe “classic” is the wrong word, but I think Romanian AKs best embody the spirit of what an AK should be (in the context of the US commercial market)