Have never played the QID and have only played the KID once... so am curious.  Any thoughts on this would be greatly appreciated!

that's a loaded question to which there is no real answer. 

It's not really a matter of which is "better" since these are not like things that could branch from the same base. The QID requires Black to start as with a Nimzo-Indian Nf6 & e6 when White dodges with 3. Nf3 and Black plays b6 (instead of Bb4+ the Bogo-Indian). If you were to ask "Which is better, the QID or the Bogo?" that would be a reasonable Question, since they stem from the same base.

The KID starts from an opening sequence with an early d6  & g6. These set in motion a very different type of game with a much "sharper" middlegame than the one you are likely to find with the QID.

now that is a very unreasonable statement you, who don't know what you're talking about. did you include reasons? any insight? no. so all you're doing is just spamming the forum with your garbage answers.

They both have their pros and cons. the qid is flexible and attacks the center with pieces, like nf6 and Bb7. it focuses solely on the center. the KID gives away the center with no fight at all, makes a flexible defense early, then later on pressure the center with e5, c5, and even Bg4 to indirectly get at the center. also f5 is a key move after the Nf6 is re maneuvered. kings indian gives you positions with sometimes bad pawn structure and less central space but monstrous attacking chances on kingside and chances to stop counterattack. 

You can't possibly compare the two.  Black can force the game into KID with normal play by both sides, whereas the QID is only a response to White's 3 Nf3.  So a real comparison would be between KID and the NID/QID complex, and the answer will always be the same:  it's a matter of personal taste. 

You can play either system aggressively as Black if you choose.  Aggression isn't from the opening, it is from the player.

I'm not an expert, but from my limited understanding, the QID works in conjunction with the Nimzo-Indian Defence as an openings repertoire system against d4 and characterised by an early e6.  If 1.d4 Nf6 2.c4 e6 3.Nc3 is played, people tend to play the Nimzo-Indian with 3. ... Bb4 whilst 3.Nf3 heads into the Queens Indian with 3. ... b6.

The KID on the other hand is a completely different repertoire system which starts with an early g6: 1.d4 Nf6 2.c4 g6.

Which is better?

Some might say that the Nimzo/QID opening repertoire system is seen more often at the higher level.  I personally like the KID, but then again I'm rubbish.

@ Bruce: Gibraltar is not in England.

LOL! Well, no wonder they lost their empire.

Oh, and I much prefer the development found in the Nimzo/QID/Bogo-Indian complex to the instant complexities of the KID.

So then, we could say that, judging by the way most people use the KID and the positions it will most often lead to, the KID is "living or dying by the sword", it is a win via a strong kingside attack, or a loss due to an inferior pawn structure and weak queenside.  In contrast, the QID is, judging by its most common variations, a more conservative opening in which black will attempt to "equalize", to match or exceed white's position with it's strength on the queenside.   Yet both will provide some great offensive opportunities and defensive structures for black.  Whereas the QUID will often lead to a draw, the KID will lead to an outright win- or loss.  I have found all of this immensely interesting- please continue...

If Black just wanted to play conservatively for equality, he could play 3 ...d5 and get back into a QGD.  The QID seeks imbalances in the position, which can lead to counterchances.

I have relied on the NID/QID complex for decades, and never was thinking of achieving mere equality - except in those games where I slipped into disadvantage.

Openings aren't aggressive; players are aggressive. 

Profound words... my friend

"Openings aren't aggressive; players are agressive."  I suppose that is true.. yet it is also true that openings come from the minds of players..

All chess by black is trying to equalize, unless you're playing an idiot.

Here is a game I played recently in which I used the KID, and my opponents mistakes, to achieve a winning position.  I know I made some minor errors, but it was my first game playing the KID..  any comments on the game?

http://www.chess.com/echess/game.html?id=53611122

Enjoy!