I'm no authority on forex brokers. At the end of the day if you're on the wrong side of the trade or when there's act of god(central bank surprise), brokers can't save you. Control leverage and place stops and hope that your broker will exit you where you placed your stops and not 100 pips away!
The closest thing that I know which can protect you when price moves against you is IG's GSLO, but they're not intended for scalpers and short term players and they're not available at reasonable distance except on the most liquid currency pairs.
If you're intraday trader betting size and need 'trustworthy' pricing, I'd stick to banks - they have better liquidity pools and counterparties. Knowing how your broker has performed when price has spiked is useful, but doesn't guarantee that the next time there's a 'major' incident their best price execution is going to save your rear. If you don't like that, move to other product - they're 'less' risky.
I know very few retail traders who are successful trading size ($50~$100/pip) intraday fx, but they trade no more than couple patterns and if they don't see a pattern, they won't trade. Most lose money intraday.
