In response to Flakbait's post, i don't think the assumptions he's made are entirely accurate-
First off, ALL ammo is mildly corrosive, but there's only an issue if you live in a humid climate and plan to crack off multiple mags of milsurp ammo and never plan on cleaning it. Even a rudimentary clean will negate the effects of corrosive ammo (I have put about 2,000 rounds of corrosive ammo through my RPK and there is nary a rust spot anywhere, and I give it a normal clean after I shoot it). If you pick up one with a chrome-lined barrel, it will negate corrosive ammo even further.
Also, compared to a Mini-14 and an AR, a $400 AK is a great deal, considering how you can fill it with sand and muck and it will still function- unless you can get a hold of said $100 AK for me
And a friend of mine picked up an RAA Saiga 7.62 AK, and he just took his first buck with it... at 400 yards. Which don't get me wrong was a STRETCH for that, but still effective. At that distance I would be hesitant with a 7.62X54R, but I guess different strokes. My RPK can consistently make hits outwards of 200 yard open sights, regardless. I'm actually more comfortable with making hits at that range than either of my Mosin-Nagants (one of which is PU scoped).
A lot of the new Century gun have seemed to address the quality issues such as canted gas blocks, mag wobble etc. So I would say get an AK and don't look back. Later on when you have the cash, pick up an AR if you feel you need to glean a little more accuracy out.