I've had no less then three masters play the London against me. It's not just a good choice for amatures looking to avoid theory. Many (mostly older) masters want to avoid prepared lines and theory battles when playing down, and the London is a fantastic way of doing such. 

I managed draws in those three games without ever feeling a lot of pressure, but I used to play the London and I know what to watch out for. I've seen friends of mine (expert+ as well) lose against the London, usually due to endgame mistakes or other mishaps in technical positions. 

If you're a good techincal player who is willing to grind out a 60 moves in an equal position waiting for mistakes then the London is nice low-risk choice.

If you're a great attacker who thinks the London will get you beautiful sacrifice attacks on h7 all the time you've been mislead by a fancy opening book. It's not really that hard to stop all the mate threats.

Yes this is why I will probably move on to other openings in the near future. While the London that I learned was what I played has worked out well for me and my study habits so far I'm beginning to feel "short changed" in my ability to generate attacks, especially against higher level opponents.

Indeed, 90+ percent of the time black-side (if they knows this opening) will get an equal position (against the London System) after about 10-15 moves, or sooner.  So what?

And those are the lines I study closely, using Rybka to provide insights into the tactical nuances (when I have the time).

It's all about the middlegame and endgame EXCHANGES.  Compare two books by Gennady Nesis, former World CC Champion, on Tactical Chess Exchanges (1991), and Exchanging to Win in the Endgame (1990).

I like to EXPEND all my pieces in the battle, and I'm perfectly happy entering a level endgame.  Then I play for a win, regardless of the position.   

Nothing Flashy.  Steer for the endgame, but damp down the opening surprises to a minimum.  Simple.

And leave the "opening system choreography" to the professionals.  Or just take it up LATER, after you finish your other studies of the Royal Game.

I have about 15 books queued up to study, presently.  NONE are "opening books."