Which one is better system? London (Colle) or KIA?

Depends on the person playing it.

There many variants of both systems, maybe U should post exact diagrams.

London and Colle are different, so I don't know why you've combined them. London is fine, but it's just equal in most lines. Just like the Colle. Just like the KIA. Just like most systems  

I personally really enjoy the Colle Zukertort or Yusupovka but the problem with it is that it only works in certain move orders, vs e6 systems primarily otherwise the bishop goes to f5 or g4 and becomes a pain or else black plays g6 which blunts the effectiveness of the bishop on d3. The London really is a system nowadays and is played in various ways by some top players in the world whereas the Colle, despite making an appearance in the WCC isn't played quite so often! I must confess to having never played the KIA, however opinion seems to differ as to if it is a good opening for an inexperienced player, I know Dvoretsky thought it was fine but many people consider this approach too restrictive and the opening to be too strategically complex for players starting out. Hope that helps a little

What would you rather play with White?

- reversed slav

- reversed semi-slav

- KIA which can change to reversed KID, reversed Ruy-Lopez kind of things, reversed sicilian, e.t.c;

If you have to pick one, the London System: Gata Kamsky play it regular and Magnus Carlsen has played it a few times and few GMs use it in their opening repertoire.

London!

I played the KIA as my regular White opening for years, and now play the London. I think the London has fewer weaknesses, and as yureesystem mentions, King Kamsky plays it regularly, and he's terrific. Simon Williams put together 3 videos on YouTube, BTW, and in them he states he's created a DVD for ChessBase, which they have not released yet, plus 6 or 7 videos for chess.com, which has not been released here, either (Hey! chess.com! Hint, hint!!!). That would all give you a good start.

     I vote for the London System.  When I play Black, I find it to be dangerous as mostly I play ...d5 systems as Black.

That's also nothing to do with the Colle whatsoever, since it's transposed into a line of Classical Slav

The Colle is mainly only good at the club level....it was taught to me as a beginner so I could at least get to the midgame without any serious difficulty....I play mainly KIA now and it seems much stronger in general.

KIA is my taste. Colle and London are passive IMO. Trying to win by resignation by boredom 😎

For me, definately KIA. I made it my main opening, and it carried me through four tournaments without a loss. It is not work-free though - took me about a year to become reasonably proficient in it. Plus, it helps having some experience in King's Indian Defence, in case Your opponent plays something overextended like reversd Saemish. One tried it against me over the board yesterday:

I think that there has been a lot more London stuff published lately. I suppose that that could be taken as an argument in favor of the KIA.

KIA in my opinion

KIA will enable you playing the first six moves (maybe seven) on autopilot, and the rest of the game at random.

lol. But to be fair you can do that for anything else too xD

The KIA is discussed in Winning Chess Openings by GM Yasser Seirawan.
https://web.archive.org/web/20140627132508/http://www.chesscafe.com/text/hansen173.pdf
For more on the KIA, one could try The King's Indian Attack: Move by Move by Grandmaster Neil McDonald. Perhaps, it would be of interest to look at The Fianchetto Solution by Emmanuel Neiman and Samy Shoker.
https://www.newinchess.com/Shop/Images/Pdfs/9029.pdf

"... For players with very limited experience, I recommend using openings in which the play can be clarified at an early stage, often with a degree of simplification. To accomplish this safely will take a little study, because you will have to get used to playing wiith open lines for both sides' pieces, but you can't eliminate risk entirely in the opening anyway. ... teachers all over the world suggest that inexperienced players begin with 1 e4. ... You will undoubtedly see the reply 1 ... e5 most often when playing at or near a beginner's level, ... After 2 Nf3, 2 ... Nc6 will occur in the bulk of your games. ... I recommend taking up the classical and instructive move 3 Bc4 at an early stage. Then, against 3 ... Bc5, it's thematic to try to establish the ideal centre by 4 c3 and 5 d4; after that, things can get complicated enough that you need to take a look at some theory and learn the basics; ... Of course, you can also play 1 d4 ... A solid and more-or-less universal set-up is 2 Nf3 and 3 Bf4, followed in most cases by 4 e3, 5 Be2 and 6 0-0. I'd rather see my students fight their way through open positions instead; however, if you're not getting out of the opening alive after 1 e4, this method of playing 1 d4 deserves consideration. ... a commonly suggested 'easy' repertoire for White with 1 Nf3 and the King's indian Attack ... doesn't lead to an open game or one with a clear plan for White. Furthermore, it encourages mechanical play. Similarly, teachers sometimes recommend the Colle System ..., which can also be played too automatically, and usually doesn't lead to an open position. For true beginners, the King's Indian Attack and Colle System have the benefit of offering a safe position that nearly guarantees passage to some kind of playable middlegame; they may be a reasonable alternative if other openings are too intimidating. But having gained even a small amount of experience, you really should switch to more open and less automatic play. ..." - IM John Watson in a section of his 2010 book, Mastering the Chess Openings, Volume 4

London material that is possibly of interest:
https://web.archive.org/web/20140627074459/http://www.chesscafe.com/text/hansen85.pdf
http://www.gambitbooks.com/pdfs/Win_with_the_London_System.pdf
https://www.newinchess.com/Shop/Images/Pdfs/9035.pdf
https://www.newinchess.com/Shop/Images/Pdfs/7619.pdf
https://web.archive.org/web/20140627100246/http://www.chesscafe.com/text/hansen139.pdf
https://web.archive.org/web/20140708093403/http://www.chesscafe.com/text/tips.pdf
https://www.newinchess.com/Shop/Images/Pdfs/7656.pdf
https://www.chess.com/article/view/the-perfect-opening-for-the-lazy-student
and there is also the Cyrus Lakdawala book, First Steps: The Colle and London System.
https://www.chess.com/article/view/how-to-understand-openings

Some places are now selling a set of London System DVDs by GM Damien Lemos. I understand that there will soon be a GM Simon Williams DVD on the same subject.