Of course the Saiga line of Russian manufactured rifles are sporting weapons when they are imported into the US.
To make them look like AK's they must then comply with US laws for the proper number of US made parts. They still do not have dimples on the mag well.
The Saigas are excellent rifles and make great donor rifles for conversion.
It takes a lot of money to transform it correctly.
With the last point and the fact that you then are reliant upon a decent builder to transform it I would reccomend that you choose another rifle for purchase if it's your first or only AK.
What I would suggest is the Bulgarian manufactured Arsenal rifles
www.arsenalinc.com/about.htm depending on what caliber you want I would suggest the 5.45
SLR-105a1rI personally have nothing against the Vulcan product line as I have no experience with them, but I have never heard anything bad about an Arsenal.