That cannot be answered if you don't provide your intent for the gun, if you want to duck hunt then don't buy an sks, if you want to deer hunt and shoot 200 yards don't buy a shotgun (though the sks wouldn't be my first choice either), home defense I'd go with a shotgun
Vote Scott Walker for Governor June 5th 2012
If your going start collecting, buy quality guns. You'll appreciate your collection and your collection will be worth more if you had to sell. But if you building up a personal arsinal, I would buy the SKS first. Only reason is because they are getting more expensive.
The reason i ask is because me and my stepdad keep our guns in the same safe so we share guns , we have a shotgun already but no sks i do not yet own a shotgun of my own but i want one because of the versatility and different uses but i also want an sks because the sks is increasing in price and they are becoming harder to find and its the only semi auto military rifle thats under 800$ that i know of so wich should i buy first? Sks or shotgun?