It was a pre-ban until 1989 when importation was stopped dead in it's tracks. The M90 means it was modified in 1990 and therefore reduced it's value. I have a Mitchell pre-ban folder that I purchased in 1988 and would never let it go. Supposedly only 400 were imported prior to the ban, but even less RPK's were brought in. The RPK does have a Yugo receiver, which puts it in a better class than current AK's made from parts. Yugo parts are still available, but fortunately I never needed any in 24 years. I'd rather pay $1400 this Ak than $1600 for a Bushmaster, or other parts gun.