I think an SKS is a better gun to start with. Less expensive, easier to learn how to use, easier to control. Usually more accurate.
But if you want to fire mag after mag as fast as you can, go for the AK, as too much rapid use will wear out an SKS. If you must use detachable mags, get an AK, as you can easily get into legal hassles with the SKS. If you were an engineer and an expert with the rifle, you might be able to get around it, but you'd have to learn what you're dealing with first. Nice thing about the SKS is that there's so much you can do with it.
Of course, you can get the best of both worlds if you're willing to pay as much as the two combined. The rifle's a VEPR II, and it's a beauty, though it's very barrel heavy. I used to want one, but am happy with my SKS-D that can use AK mags. I just don't empty mag after mag rapid fire.