The SKS is cheap to acquire and cheap to feed for a lot of plinking and a semi-auto carbine certainly does introduce variety into your selection for hunting. The cartridge is generally taken to be alike to the .30-30 in effective range and killing power, and if you reload you have a better selection of bullets than the round or flat noses needed for the tube magazines on the lever action guns most common in .30-30. The accuracy of any particular SKS may not give the same effective range as many .30-30s, but you'll have to get one and try it to find out.
If the power and range isn't sufficient for the game and terrain on a particular hunt, you have your .270 and 7mm Magnum. If you don't like your SKS as much as you hoped, you'll not have much trouble selling it on and getting most of your money back, as long as you don't pay over the odds to begin with or spend too much customising it.
