Slippage for large orders: How bad is it?

This question is for live traders who have traded more than 1 mill size orders (10 lots).

What is your experience with slippage with that kind of order size?
Does the FX market ever get illiquid enough over the short term to make even a 1 mill stop loss order risky?
Is it possible to get out of a position at close to the market price with that size even during fast moving markets such as NFP or interest rate announcements?
If, yes with what kind of size would it start getting difficult to get out of a position?

In short, I am trying to get a sense of how liquidity is distributed over the short-term in FX. The trillions of dollars of volume are not much use if there are major liquidity gaps that occur when a trader need to liquidate a position.

I dont see $1million as an issue over any news announcement however it depends on your broker with how they have set up their liquidity.

MT4 is top of book and brokers tend to get $100k pricing from Lp's to give them a tighter price but this is useless for someone trying to execute $1m.
You are bound to get slipped or not filled.

You need to seek out a broker that caters for Institutional style trading and be asked to be put on that stream.

10 lots is nothing my friend , market maker can handle this in less than seconds. now if you were talking 1000 lots or 5000 lots then might be a different story. Your broker has a max lot size for a reason.

I used a scalping method to take advantage of some of the inefficiencies of the market, while it did extremely well in the beginning (turning over 800% return), eventually my position sizes got too big and that's where I ran into liquidity and slippage issues. Essentially it all depends on your system. If you use big position sizes to scalp just a few points, then slippages of a few points here and there will totally ruin the positive expectancy.

10 standards lot?
No problem at all