Take a look at excel markets, they are based in New Zealand though ... regulated by the New Zealand Financial Markets Authority and offer less than a pip spread on most fx pairs. Pretty impressive.
I'm not sure how fast any regulator can move in the event of a problem with a particular broker, but FMA issues 'Latest Warnings and Alerts' here http://www.fma.govt.nz/keep-updated/...gs-and-alerts/ and a list of non-compliant firms and individuals here: http://www.fma.govt.nz/keep-updated/...-to-be-wary-of
I'm not sure how fast any regulator can move in the event of a problem with a particular broker, but FMA issues 'Latest Warnings and Alerts' here http://www.fma.govt.nz/keep-updated/...gs-and-alerts/ and a list of non-compliant firms and individuals here: http://www.fma.govt.nz/keep-updated/...-to-be-wary-of