It's lots of short shots here, thick woods a lot of the times and if you move quiet you're apt to see him before he sees you at pretty close. I can't see an SKS and good hunting ammo having ANY problems killing deer if you put one through it's chest.
I think the biggest problem is how far out you can get it done with the irons (assuming we are not talkin anything ridiculous here) but then again, when ain't it?
All the other guys here said not there first choice either, and I gotta echo them. Even as far as mil surps go, and that's not so much a knock against the SKS as I prefer the irons on Garands, 14s, and other aperture style sights more.
Again tho, I shoot 90% of my deer inside 100 meters and 50% of those at 50m or less.