I have quite some experience on this as I never really wanted to study "real" openings and have quite a good endgame tecnique (for my level of course). Objectively black is absolutely fine and really could even have some slightly better prospects as d4 is weakend for ever.
However I think this is one of those openings were the real evaluation isn't that important for the following reasons:
-the guy playing white may as well play this stuff every time he can while as black you may have to confront with it at most once or twice a year: white has more "thoeretical" knowledge (ok, there isn't really much theory but white probably knows the existing better) and has a better idea of what to do and how to try to squeeze the position for he has more experience;
-when you play the KID as black you simply want to give a a piece or two near the white king, let white's d-pawn reach d7, loose all your queenside pawn and possibly the rook to give an amazing mate (I may have exaggerated but...). Therefore when black discovers he's going to fight in a queenless middlegame there's a good chance he'll go to the toilet and cry (ok... again to much... but I must say I have seen many players disappointed or angry after mere 8 moves): it's just not what black expected.
-black may be biased from books such as "Refuting 1.d4 with the KID" or similar and think that if white plays this variation he wants to achieve a draw and go home to see a football match: NOT TRUE! I played it to win for one. Therefore the attidute "anything goes, I'll just play a few moves, offer draw and go to the pub" is quite common. Often my opponents "confessed" that they assumed the game to be over after 8 moves without realising that they lost 0.02 pawns for 25 moves in a row
So in conclusion in my view black is ok as long has he knows a little (very little!) theory, has a decent understading of the positions arising and actually plays the game instead of making automatic moves in a depressed mode thinking it will be a quick draw.